There's a funny thing about experience: It doesn't always make you immune to failure. In fact, some of the most seasoned, intelligent founders I've met — including myself — have walked straight into the same fire multiple times, thinking this time would be different.

After buying, building, burning and selling businesses ranging from $1 million to over $20 million in annual recurring revenue, with teams as small as five and as large as 500, I've seen these mistakes up close. Not once. Not twice. But over and over. I've made them myself. I've watched peers make them. And most frustratingly, I've watched incredibly smart entrepreneurs make them while fully aware of the warning signs.

Why does it keep happening?

Because we convince ourselves that this time is different. We raised more capital. We're in a new vertical. The economy has shifted. We've got better advisors. But these so-called differences rarely change the fundamentals. These mistakes don't care about your funding round, your pitch deck or the decade you're building in. They always find a way to show up ... unless you deliberately learn to recognize and avoid them.

Here are the top five mistakes smart entrepreneurs keep making — because intelligence alone isn't protection.

Related: 5 Common Entrepreneurial Mistakes There Is No Excuse for Repeating

Smart founders love strategy. We love architecture, systems and layered thinking. But too often, that intelligence leads us to outsmart ourselves by overcomplicating something that should've stayed simple.

In one of my earlier ventures, we created an onboarding system so "intelligent" that it required a five-step identity verification, AI scoring and three user roles. It was technically perfect — and completely unusable. Not a single customer made it through the first interaction without needing help. We had engineered a fortress when all the customer needed was a front door.

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