If you’re leading marketing at a big ecommerce brand right now, there’s a very good chance you’ve heard some version of this pitch from an agency in the last twelve months:

We do omnichannel.

Great. So does everyone with a deck, a media plan, and enough confidence to say it without laughing.

The problem isn’t that agencies talk about omnichannel marketing too much. The problem is that a lot of them still don’t know how to do it without turning it into a very expensive coordination exercise that makes everybody feel productive while the actual business impact gets blurrier.

That’s where things start costing you.

Because when omnichannel is run badly, you rarely see big Michael Bay-esque explosions. Instead, omnichannel fails in the slow, annoying, budget-draining way that’s much easier to miss at first.

Why? On the surface, it all looks good!

Each channel has a narrative. Each team has a report. Each partner has a point of view. Everybody’s got a graph. Everybody’s got a reason. Everybody’s got a “we’re seeing strong engagement” update that sounds respectable enough to keep the machine moving for another week, another month, another quarter.

Meanwhile, you’re the one sitting in the middle of it trying to answer the question that actually matters:

Is all of this working together in a way that’s growing the business, or am I funding an agency that’s giving me a very well-documented mess?

That’s the real omnichannel question.

It isn’t, “Are we on multiple platforms?” It isn’t, “Did we launch the campaign across paid social, search, email, retail media, and connected TV?” And it definitely isn’t, “Do we have a unified reporting deck with a lot of color coding and arrows?”

Those things can all be true while the campaign is still being run poorly.

Real omnichannel marketing isn’t just “more channels at once.” It’s the discipline of making channels work together in a way that improves business outcomes instead of muddying them. It should create reinforcement, momentum, better handoffs, better timing, better learning, better allocation, and better performance than any single channel could deliver on its own.

When that isn’t happening, you don’t have an omnichannel strategy. You have channel sprawl. And a lot of agencies are much better at selling channel sprawl than they are at fixing it.

So let’s talk about the mistakes your agencies are making right now. The real ones. The ones that sound smart in meetings, look fine in reports, and quietly cost you money.

Mistake No. 1: Your agency is treating omnichannel like a distribution plan, not a decision system

This is probably the most common mistake, and it’s a big one.

A lot of agencies treat omnichannel planning like the job is finished once the campaign has been spread across enough surfaces. Search is live. Paid social is live. Email is queued. Display is running. Maybe influencer is in the mix. Maybe retail media got bolted on because someone wanted to look “full funnel.” Everyone nods because the campaign is now, technically speaking, everywhere.

That isn’t strategy. That’s channel placement.

A real omnichannel campaign isn’t just about where the message shows up. It’s about how each channel is supposed to contribute to the decision journey, what each channel is supposed to do better because the others exist, and how the entire system will be evaluated once customers start moving through it.

If your agency can’t answer those questions with any depth, what you’re looking at isn’t omnichannel marketing. It’s media diversification with a nice outfit on.

This mistake gets expensive because disconnected channel plans tend to create one of two bad outcomes. Either channels duplicate effort and you pay multiple times to tell the same story in slightly different ways, or channels compete with each other for credit and no one learns anything useful about what’s actually driving the sale.

In both cases, your spend gets less intelligent over time.

You don’t need an agency that can simply “activate across channels.” You need one that understands how the channels should work together, what role each one plays, and what tradeoffs come with that role. Otherwise, you’re not getting orchestration. You’re getting parallel play.

Mistake No. 2: Your agency is optimizing each channel to look good on its own

This is how a lot of omnichannel campaigns slowly rot from the inside.

Every channel lead wants their line item to look efficient. Fair enough. That isn’t an irrational instinct. The problem starts when the agency optimizes each channel as if its job is to win a beauty pageant instead of contribute to a system:

And guess what happens next?

You might be tempted to call that bad luck, but it’s not. This is exactly what happens when channel optimization is allowed to outrun business logic.

An omnichannel campaign is supposed to help you understand how demand is created, reinforced, captured, and converted. But if your agency is grading each channel on isolated efficiency instead of system contribution, it’ll keep overvaluing the closers and undervaluing the creators.

That costs you twice. First in wasted budget allocation. Then again in the false confidence that comes from those pretty little channel-specific wins.

And if you’re in the seat responsible for growth, that false confidence is expensive as hell.

Mistake No. 3: Your agency still hasn’t figured out what each channel is actually for

This sounds basic. You’d think this one would be solved by now. It isn’t.

A lot of agencies can tell you what channels they use. Fewer can tell you, with real clarity, what each channel is supposed to do in your specific business at this specific moment.

This is a big deal because:

Basically, your channels aren’t destiny. Their role depends on the audience, the creative, the offer, the product, the timing, the business problem, and how the rest of the system is working.

Bad agencies rely on generic channel mythology. Good agencies actually diagnose.

If your agency is still making lazy assumptions about channel roles, your campaign is going to reflect that laziness. Messaging will get flattened. Measurement will get distorted. Budget will move toward familiar defaults rather than actual opportunity. And the entire omnichannel plan will start looking less like strategy and more like a category cheat sheet somebody recycled from another client.

Mismatched channel roles create bad expectations. The wrong success metrics get applied. The wrong creative gets developed. The wrong timelines get imposed. Then channels get judged unfairly, investment gets pulled too early, and the campaign never gets the chance to teach you what it could have taught you.

A lot of “channel underperformance” is actually expectation failure in disguise.

Mistake No. 4: Your agency is running one creative idea into the ground and calling it consistency

Let’s talk about one of the great modern agency sins: confusing repetition with orchestration.

Yes, omnichannel campaigns need consistency. The customer should feel some continuity as they move from one touchpoint to the next. But continuity isn’t the same as sameness, and way too many agencies still behave as if “integrated creative” means taking one message, one visual idea, one set of headlines, and smearing them across every platform until the campaign dies of boredom.

This is what we in the business like to pretend is creative strategy, but is actually something we like to call “lazy asset deployment.”

(Yes, that’s the technical term. No, I won’t be taking questions.)

Different channels ask different things of creative. Different contexts change how the message lands. Different stages of intent need different persuasive moves.

More specifically, the ad somebody sees while thumbing through social with half their brain online shouldn’t sound exactly like the email they get after visiting product pages twice and abandoning a cart.

If your agency is using “consistency” as an excuse not to think harder, it’s costing you.

Because creative fatigue shows up fast when the same idea gets shoved into every context with no sensitivity to the moment. Customers tune out. Message relevance drops. Performance softens. Then somebody decides the channel is the problem when the actual issue is that the campaign has been speaking in one flat voice no matter where the customer encounters it.

Real omnichannel creative isn’t one idea repeated without imagination. It’s one strategic throughline translated intelligently across contexts. That takes more work. Which is exactly why weaker agencies try to get away without doing it.

Mistake No. 5: Your agency is reporting on channels, not on the customer journey

This one is huge, and it drives me crazy.

If your omnichannel reporting still looks like a pile of channel snapshots stacked next to each other, your agency isn’t giving you omnichannel intelligence. It’s giving you separate book reports.

Search says one thing. Social says another. Email says another. Retail media has its own deck. Maybe there’s a nice summary slide at the top where everyone pretends these pieces naturally resolve into a clear story.

But they often don’t.

Because customers don’t experience your marketing as channel reports. They experience it as a messy series of exposures, reminders, nudges, comparisons, hesitations, and returns. They see something on one platform, click on another, research elsewhere, come back direct, get an email, ignore it, then convert through branded search or retail media and make half the system feel invisible in hindsight.

That’s why omnichannel reporting has to work harder than single-channel reporting. It has to help you understand how channels reinforce each other, where sequencing is working, where fatigue is building, where overlap is wasteful, where assist value is real, and where channels are getting too much or too little credit.

If your agency keeps handing you channel-by-channel recaps and acting like that’s enough, you’re not getting the level of thinking you’re paying for.

And that costs you because channel-only reporting naturally pulls decision-making toward channel-only optimization:

Stop settling for agencies who only give you dashboard furniture, rather than real reporting.  You need someone who can help you see the system.

Mistake No. 6: Your agency is making “full funnel” the excuse for weak accountability

There’s a version of omnichannel marketing language that sounds very sophisticated right up until you realize it’s being used to avoid hard questions.

You’ve probably heard some of it already.

We’re building awareness at the top. We’re surrounding the customer across touchpoints. We’re driving consideration across the funnel. We’re playing the long game.

Okay. Maybe. But what are we actually learning? What’s improving? What isn’t? Where is the handoff working? Where is it breaking? Where is spend earning the right to stay? Where is the strategy too vague to challenge?

This is where some agencies hide behind “full funnel” language because it gives them a lot of conceptual room and not a lot of immediate accountability. If every channel is part of some beautifully interconnected customer journey, then any weak performance can be brushed off as necessary support for something else.

That’s convenient. It’s also dangerous.

Because omnichannel does require patience in some cases. It requires looking beyond last click. It requires understanding delayed effects and assist value. But that isn’t the same thing as granting every tactic diplomatic immunity from scrutiny.

A good agency can hold two thoughts at once. It can respect the complexity of the system and still be very honest about what’s underperforming, what’s learning, what’s directionally promising, and what’s mostly being kept alive by hope and presentation skills.

If your agency uses omnichannel complexity to make the campaign harder to question, that’s costing you. Not only in spend, but in time. And wasted time inside a bad campaign is sometimes more expensive than wasted media dollars because it delays the fix.

Mistake No. 7: Your agency is treating coordination like strategy

A lot of omnichannel campaigns get praised for being “well coordinated.”

Sure. Great. Awesome.

The launch calendar is aligned. The teams are talking. The assets were delivered. The channels went live on time. Everyone has the same key visual. The email landed the same week the paid social push began. Maybe there was even a Slack channel.

That’s operations. Useful operations, yes. But still operations.

Coordination isn’t the same thing as strategy or effectiveness. A tightly coordinated bad idea is still a bad idea. In fact, it can be worse, because now the bad idea is everywhere at once and more expensive to reverse.

This is something you need to watch out for, because agencies love to present seamlessness as proof of strength. Look how integrated it all is! Look how clean the rollout was! Look how every moving part aligned! Just… don’t look too closely at the results. 

And then you do start looking at the results, and asking yourself the tough but necessary questions:

Without them, “integration” becomes a kind of adult arts-and-crafts project. Lots of teamwork. Lots of planning. Lots of sticky notes. Not necessarily better outcomes.

Mistake No. 8: Your agency isn’t honest enough about overlap, waste, and diminishing returns

This is where omnichannel gets uncomfortable, which is exactly why weaker agencies avoid it.

When you’re active across multiple channels, overlap is inevitable. Sometimes that overlap is good. Reinforcement matters. Repetition matters. Familiarity matters. The issue isn’t overlap itself. The issue is whether anyone is being honest about when overlap stops being helpful and starts becoming wasteful.

That’s a harder conversation, especially when different teams or channel leads all want budget, all have a narrative, and all can point to some metric that makes their work look necessary.

But if your agency isn’t digging into duplication, saturation, diminishing returns, and frequency across the system, it’s costing you.

You may be paying to chase the same audience too aggressively in too many places. You may be overexposing the same creative. You may be saturating one segment while underfunding another. You may be creating the illusion of omnipresence while actually just annoying the people already closest to buying.

And because each channel has its own internal logic, it can be surprisingly easy for agencies to miss this or, worse, politely ignore it because the conversation gets political.

That isn’t good enough.

Part of omnichannel strategy is knowing where enough becomes too much. Where reinforcement becomes redundancy. Where “staying present” becomes crowding the customer. Where spend should be rebalanced because the system is no longer getting smarter from sheer repetition.

If your agency never seems to find those thresholds, you should ask why.

Mistake No. 9: Your agency is using AI to speed up noise instead of sharpen decisions

We’ve reached the point where nearly every agency claims some version of AI-powered omnichannel intelligence.

Hi, we’re one of them. We use an intelligence layer called Prism AI that helps us make smarter decisions faster, shore up testing inefficiencies, and spot shortfalls before they become money pits.

But (and this is a big but), Prism AI isn’t the leader. Our elite strategists are. Our clients are. And we have agentic engineers (who are essentially AI-native marketers) who are constantly working with our technology to refine, improve, build, and perform better.

So, yes. AI can help teams move faster through data, flag patterns earlier, speed up reporting, support creative testing, improve workflow, and reduce a lot of the manual drag that used to slow down perfectly smart people.

That part is real.

The problem is that some agencies are using AI the way a teenager uses cologne: 

Way too much, for the wrong reasons, and mostly to create the impression that something sophisticated is happening:

If your agency is using AI to generate more messages, more reports, more variants, more budget moves, and more “insights,” but the core strategic questions are still muddy, then congratulations: you’re now scaling confusion more efficiently.

That costs you because AI can make a weak system look busy and advanced for longer than it otherwise would. It can produce the appearance of intelligence while the actual decision-making remains thin. And in omnichannel marketing, thin decision-making gets expensive fast because complexity multiplies mistakes.

AI should make the work smarter. It shouldn’t make the nonsense arrive sooner.

Mistake No. 10: Your agency isn’t building a campaign that teaches you anything

This is the mistake underneath all the others.

A strong omnichannel campaign shouldn’t just run. It should teach.

It should teach you which channels reinforce each other. Which creative ideas travel well across contexts. Which audiences need repetition and which ones need a sharper message. Which stage of the journey is soft. Which objections keep appearing. Which investments create lift beyond their last-click footprint. Which channels are carrying more weight than they seem to be getting credit for. Which parts of the system are expensive because they’re necessary, and which are expensive because no one has been brave enough to cut them.

That’s what a good campaign gives you in addition to performance.

Too many agencies never get there because they’re so busy keeping the machine fed that they forget the point isn’t just to launch activity. The point is to build a more intelligent growth system over time.

If your agency runs omnichannel campaigns that leave you with a lot of spend data but very little sharper understanding of your business, your customers, or your growth mechanics, that’s costing you. Maybe not just this quarter, either. It’s costing you compounded learning.

And that’s one of the most expensive things to lose.

So what should omnichannel marketing actually feel like with the right agency?

As you can tell, I’m a girl who loves a good list, and this right here seems like the perfect spot for one.

Most of all, it should make the system better than the sum of the parts.

That’s the whole promise.

If your agency is truly good at omnichannel marketing, you should feel that in the quality of the decisions, not just the quantity of the activations. You should see it in the reporting, the creative strategy, the way budget gets moved, the honesty around tradeoffs, the clarity around what each channel is doing, and the ability to tell the difference between real reinforcement and expensive redundancy.

If you’re not getting that, then “omnichannel” is probably just the word your agency is using for “we run a lot of stuff.”

And yes, that is costing you.