5 Fatal Startup Mistakes -- and How To Avoid Them Where countless entrepreneurs find success, others have found failure. Here is why.

I've worked with a lot of startups over the years, and I've seen countless entrepreneurs find success where others have found nothing but failure. Among those who have struggled the most, I began to see common threads (even successful startups have fallen into some of these entrepreneurial traps) and only through incredible determination did they rise above and prevail.

Here are the five most common fatal startup mistakes and how you can avoid them.

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1. Questioning yourself at every turn

Starting a business can be scary, and the amount of unknown variables as you continue forward are daunting -- even for the most seasoned entrepreneurs. It's easy to second guess yourself as the challenges pile on, but it's important to stay stead-fast in your ideas. If you're not confident about your startup, why should anyone else be -- including your investors, customers, and employees?

Obviously, arrogance can be a slippery slope but tell yourself whenever necessary that your idea has the potential to make a difference and help many people. Projecting positivity and confidence is infectious, and it can be the push you need when building relationships. Whenever you have doubt, just remember that others have come before you, and if they can make it, there's no reason you can't.

2. Biting off more than you can chew

There's no feeling quite like landing that first big client. It's a great moment, and you deserve to congratulate yourself. That said, too many times I have seen a startup get that client and grow too rapidly to accommodate.

Take things at a decent pace and don't push growth where it can't reasonably happen. With that in mind, make sure you have a concrete plan of action in which to operate from. It's imperative to have measurable goals to understand where you're going, and know when you're off course. Don't tackle projects that can't realistically be completed within set parameters. Understand your limitations as a new company - you'll be running with the elite soon enough.

3. Lacking a social-media presence

It's upsetting how often I see startups avoid social media, considering how easily it can be fixed. It's such a simple way to reach out to people, yet some companies take too long to get onboard. Facebook, Twitter, LinkedIn -- whatever medium you prefer -- create an account for your brand and use the platform to engage with others. Being consistent and adding value are the two most important things to remember when using social media.

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Also, I see too many entrepreneurs using social media the wrong way. They put up a few posts on LinkedIn or send out a few tweets and expect instant results. Think of social media as a crockpot rather than a microwave. It'll take a while to pay off but when it does, the final product will be excellent.

I have an entrepreneurial friend who has over 550,000 followers on LinkedIn. I asked him what his secret was. His answer? "I do two things: I post pertinent articles across all social media every day, and I engage with my followers." In this day and age, foregoing a social media presence is one of the largest -- and most easily avoidable -- mistakes any startup can make.

4. Expecting anything to be handed to you

Being an entrepreneur and starting a business requires the help of others, plain and simple. No one builds an empire alone. Still, any entrepreneur can attest to the fact that you absolutely cannot expect anything to be handed to you.

Starting a business requires more work than I can iterate through words and a strong work ethic is mandatory. This isn't to say that you won't receive any help (more on that soon) rather, entrepreneurs absolutely have to be willing to put forth everything they've got. While your friends are enjoying happy hour on a Thursday night, you're still at your office cranking out some last-minute emails. Everything starts and ends with you, and that's exactly the way entrepreneurs like it.

5. Not taking advice

This is the counterpoint to the above point. You can't expect anything to be handed to you, but on the other hand, going solo all but guarantees failure. Have a mentor. Even if you have no idea who to consult, keep networking, making connections and reaching out to people. You'll amass a wealth of knowledge and insight as you continue to develop connections that'll prove to be invaluable time and time again. Best of all, these connections will directly work wonders for your business. Not only have you learned from vetted entrepreneurs, you've built a relationship that'll continue to grow for years.

Not sure how to obtain a mentor? Find individuals who are doing what you want to do and ask to buy them lunch. Even though this sounds obvious, you'd be surprised at how many people don't do this. Mentorship is a two-way street. While you'll be receiving invaluable information, the mentor will feel empowered by giving back and helping you. It's a win-win situation for everyone involved.

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