Entrepreneur is a broadly defined term. Kids selling lemonade are entrepreneurs. Someone selling widgets at Etsy and supporting themselves at $40,000 a year are entrepreneurs. Co-founders taking a small seed to build a new app to huge traction and selling to Facebook (FB) down the road for $10 million are entrepreneurs. Someone building a SaaS business to $10 million a year in recurrent revenue, profitably, and without funding, is an entrepreneur.

The idea, though, that anyone can achieve great wealth and independence through entrepreneurship is what’s overhyped and glorified. Learning to be a great entrepreneur is a long road.

Twenty years in, I like where I am and have done well: my first business did $100,000 a year, and I sold it for $4 million at 21. My second business did $6 million a year, profitably, and I sold it for $34 million at 34 (as the sole owner with no debt). What I’ve learned along the way has positioned me to make much better decisions now, about what I want to do next and about how to manifest the best ideas into reality— far better than I would have 20 years ago. The point is, though, it has been a long, multi-decade journey: it does indeed take 10 to 20 years to become an “overnight success.”

There are so many pitfalls with entrepreneurship that it’s no wonder that it’s fraught with peril. It’s very hard to navigate your own venture successfully over multiple years. Those that do it well are called out as shining examples of how great it can be, but for every one of those, there are thousands who didn’t do well.

Here is some of what I’ve learned along the way, for those who are contemplating a life of entrepreneurship:

• Everyone has ideas. Choosing what to work on is so incredibly important. Don’t go chasing the first thing that pops into your head. Does it solve a real problem for a sizable market? How will it make money? How much money will you need to get to a minimally viable product and see if you can get traction? How will you market it? How long will it take before you’ll know if it’s a hit or a miss? Do you have deep knowledge of the industry? Take your idea and expand it into its multitude of parts: how will it work, who will build it, what’s the competition, where is the market headed. Try to kill the idea as soon as you can. If it stands up to scrutiny, you might have a winner, and after you go through that process, you’ll have a much clearer picture of whether or not you can pull it off.

• Entrepreneurship cannot be taught. The tools of the trade can be taught. How to raise money, how to read a term sheet and balance sheet, are teachable, yes. The core of being an entrepreneur, making great decisions, being obsessively dedicated to steering a business to growth, is instinctual. One learns to be good at this through trial and error and sometimes through mentorship.

• The goal of raising money and then selling in 12 to 24 months is often what they teach in school that entrepreneurship is about. It isn’t. It’s about creating sustainable, long-term value. If you’re building something to flip to Google (GOOG) (meaning, your ultimate “customer” is Google or Facebook, not thousands of enterprise businesses or millions of consumers), the odds of you crashing and burning are a lot higher than if you’re developing something to create value and to sustain itself long-term. Reason being, if you don’t get an exit, you can still be earning millions annually, especially if you bootstrapped.

• Pursue businesses that market themselves and leverage free marketing opportunities (like Kickstarter), because the alternative is an expensive and multi-year slog. Meaning, if you create a product or service and put it out there, will it be easily found by large numbers of people who are organically seeking it out, or will you be able to partner with companies (or the media) who will evangelize your product or service? Or, will you spend 5 years trying to get people to pay attention to what you’re doing?

• Get as far as you can on your own without raising money. Don’t assume that starting a business = pitching to a VC. Starting a business means creating a product or service of value: go do that.

• Think big and build things that matter. 5 years later, you’ll be happier to be spending your time on something that actually matters to you and to the world.

This question originally appeared on Quora: Is entrepreneurship over-hyped and glorified?

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