This article originally appeared in Inc. If you like this article,

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In a recent strategic planning session, my communications agency realized a pattern among the past few years of client work: we do our best work, produce the most prolific results, and have the easiest time with organizations that do not have a Chief Marketing Officer.

When we took a step back to ask why that is, we ended up with a fascinating list of reasons why today's CMOs are actually disadvantaged when it comes to creating measurable marketing results (i.e., revenue growth) for their own organizations. Looking at the list, we instantly realized why the CMO position is the one that has the lowest average tenure among C suite positions.

However, the most important revelation we had is that CMOs and their equivalents don't fail because they're bad at their jobs; rather, they are typically set up to fail, given the combination of internal organizational needs and the frenetic pace of today's best practices in marketing.

Here's why your internal marketing people might not be delivering the results you need in the boardroom (and why, as you'll see, it's mostly not their fault):

1. They Lack Scalable Expertise

Today's best CMOs are usually general strategists who have either risen through the ranks of an organization or perhaps served at a marketing agency in an oversight role. But, no matter how much the CMO reads, studies, attends conferences or confers with agencies, they can never be a subject matter expert in every facet of the marketing suite.

This naturally makes it challenging for them to understand which data to focus on, which agency's recommendations to believe, and which trends to capitalize on in the coming year.

Now take into consideration a typical CMO's internal job requirements of reporting, managing an internal team and more, and it's easy to see why their subject-matter expertise simply isn't scalable to the point where they can provide true strategic insight to the executive team.

2. Today's Marketing Requires an Omnichannel Presence

Related to scalable expertise, today's best marketing requires an integrated, omnichannel presence. Just as the typical CMO can't know everything about every creative opportunity and every emerging trend, a typical CMO also can't responsibly know about every marketing channel from traditional to digital to social media to PR to shopper marketing to experiential and more.

This naturally pulls the CMO into their comfort zone; in fact, when we sometimes ask marketing leaders why they have made certain choices about media types, they'll say things like, "I understand PPC better," "I can visibly see the ads on TV," or, "it's what we've done for years."

Sadly, none of those explanations will help an organization add measurable growth to the top and bottom line in an increasingly noisy world.

3. They're Battling Internal Politics

One of the most obvious disadvantages of a CMO is that -- once they're on the inside of an organization -- they are subject to the internal politics of the organization.

Tragically, we've seen CMOs waste countless hours with loudly insistent departments (that are not strategically significant but want marketing materials anyway). We've also seen CMOs succumb to their fellow executives' picking sides, their CEO playing favorites, and their boards outright thwarting the efforts of the CMO for some political reason or another. Most appalling, we always see CMOs spend the majority of their time explaining and defending decisions, leaving them precious little time to actually move marketing initiatives forward.

Unfortunately, as long as humans run the business world, CMOs on the inside will always be subject to internal politics, which naturally pulls their attention away from much more important things (like the job they were hired to do).

4. They Naturally Have Opposing Priorities

Finally, when it comes to producing measurable results, CMOs are set up to fail because their priorities can never be fully aligned with those of the organization.

What an organization needs is an independent, expert voice to blast through politics, hold up an honest mirror, and provide the organization with an evolving vision for a better future (or a warning about a worse future if the organization doesn't make critical changes). That independent expert must also maintain the freedom to both criticize and praise the executive leadership team as they make key decisions.

However, as long as the CMO wants to keep their job, they can never speak freely, provide an independent vision, drive necessary change, or otherwise disrupt the organization for which they work.

This same principle explains why you can't be your own therapist; it takes an outside perspective to make the change that's required. And, for better or worse, producing aggressive marketing results takes significant change for most organizations today.

So, if you're a CEO who is frustrated with your marketing results, keep this list in mind about why your internal marketing leader might not be able to get the results that you both deserve. Then consider changing your Chief Marketing Officer role to a Chief Marketing Organization that can function as an independent strategic partner and truly deliver the measurable growth you desire.