How to Know When to Change Direction There's something to be said for stick-with-it-ness, but most entrepreneurs stick with flawed ideas and plans way longer than they should.

This is Silicon Valley. Startups, founders and VCs are everywhere. You can't walk down the street in Mountain View or Palo Alto without bumping into one or two successful entrepreneurs. And yet, they usually have one thing in common: this isn't their first rodeo. In other words, their initial venture wasn't the one that stuck.

Knowing when it's time to quit and try something different is always tricky. The problem is, when you're in the middle of it, there always seems to be one more thing to try. One more customer to call. One more investor to pitch. One more credit card to max out.

That big deal is always right around the corner. Something good is always bound to happen.

There's something to be said for stick-with-it-ness, but in my experience, entrepreneurs typically stick with obviously flawed ideas and plans too long. Over the years I've seen dozens, maybe hundreds, of founders and executives stay the course far longer than they should.

And there's almost always denial, groupthink, or sugarcoating yes-men in play.

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While you always want to go about it in a practical and professional manner, here are 11 reasons to think seriously about changing direction.

Your motives were never true. Many are the reasons for wanting to do great things with your life. They can be selfish or noble, but if they're not true to you and your nature, they won't carry you through the many challenges you'll inevitably face.

The dogs aren't eating the dog food. Insanity is doing the same thing over and over and expecting a different result. And yet, companies do that all the time. When customers aren't biting, something's wrong. Time for a change, simple as that.

You're completely disengaged. If you've been demotivated or down on your gig for a very long time, it's over. There's a simple, practical reason for that. If you're disengaged, you're never going to engage customers, employees or investors.

The truth is staring you right in the face. Every company I've watched go down the tubes in agonizing slow motion – from Sun to Blackberry – had one thing in common: executives and directors living in denial. Don't live in denial. Have the courage to face the truth and deal with reality.

Related: How to Feel More Engaged and Connected

You're doing the strategy du jour thing. If nothing seems to be working and you find yourself whipsawing everyone with new strategies and plans on a daily basis, you need to stop and think about what the heck you're doing. Strategy du jour never works.

Your gut says it's over. If you're just not feeling it, chances are, you're onto something. While you can and should get advice from disinterested and experienced third parties, you should always trust your gut to make the final call.

Everyone's doing it. Look around. Is everyone and his brother doing what you're doing? If so, they're all in trouble and so are you. When the masses or what we sometimes irreverently call the fools, rush in, you need to either be the one on top or be gone. Otherwise, it's already too late.

You've come up with a way better idea. Granted, startups have to focus or they'll fail for sure. But oftentimes, that breakthrough concept – the one that ends up changing the world – is just a slight detour from the path you're already on.

You can't pay the bills. You would not believe how many wannabe entrepreneurs try to bootstrap their ventures out of greed or stupidity and end up running out of cash. If you're not realistic about finance and funding, you have no business being in the startup game.

The only option left is putting lipstick on the pig. I've been at this point with more companies than I care to remember. It happens … a lot. And unless there's something else going on behind the scenes you may have overlooked, putting lipstick on the pig always ends up being the last gasp.

You're burned out. Burnout can be serious, folks. If you're miserable or depressed, thinking bad thoughts, and it doesn't feel like you'll ever see a light at the end of the tunnel, quit and do something different.

Time and again, I've watched otherwise brilliant and capable individuals put themselves and their companies in a sort of airtight box. They can't see out of it and always end up suffocating in it. Don't ask me why, but it happens all the time. So ask yourself: Am I in a box of my own making? If the answer is yes, do something about it.

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