But the other, MUCH BIGGER issue, is that you might not know what people want. If you're building something for consumers, there's a problem in that most people don't know what they themselves want (imagine describing Facebook to someone years before it existed).

Yes, it's very difficult to predict what people want and will actually use, especially for a solo person. Asking your friends isn't enough because they will just try to make you feel good.

To underscore your point, and try to help us calibrate risks, let's examine the risks of significantly smaller projects:

• Start a blog with 500 visitors a day
• Run a Facebook page with 500 likes
• Sell 100 copies of an eBook, handmade product, or piece of art
• Create an open source software project with 100+ users

These goals are much more modest than starting a company with a mass market product, but they can still be tough for smart and talented people, and can easily use up all of someone's free time for months. And it's not guaranteed at all that someone will succeed at all in their first try at these projects.

Because executing and delivering something people give a shit about is hard. A real business is orders of magnitude more complex, risky, and time-consuming. If it's tough to make something that a couple hundred people care about, then try to imagine how tough it is to make something that tens of thousands of people care about.

Remember - Some people fail at startups built to serve an industry, after working for 30 years in that industry. They still don't manage to create a product that's good enough.

Yes. Execution is hard. Production is hard. Design and marketing are hard.

There is a big difference between class-project level execution, or demo-level execution, and professional execution that will appeal to a consumer market, especially a wide market. I believe this point has not been sufficiently emphasized in the original poster's entrepreneurship education.

Your product (rhetorical "your") is not the platonic ideal of your idea. Your project is the execution of your product. It's inseparable from the design, UI, marketing copy, and other presentational and aesthetic elements. The medium is the message.

Eventually, real consumers will face the real execution of your product, and there is an immense amount of variables involved in how they perceive it, which are really hard to predict in advance, involve the interaction of the features with design, UI, writing, etc... Predictions become really hard to make, hence, risk emerges.

And yet, restaurants fail ALL THE TIME. Because the execution of any business is hard. Hiring is hard. Understanding your market, TRULY understanding it, is hard and takes years of experience. Understanding how to hire and manage people is hard. The thousands of little things you do every day, are all amazingly hard. Each one takes time, each one takes experience.

Exactly. As another analogy, the author is like an unproven writer with a script who believe that they can make a popular movie. Or a solo game programmer believing they can make a hit game based off an idea and a demo. Yes, it's possible, but it's mega, mega risky (even creating a hit at an indie level). Even big studios with immense resource often fail at creating hits, because giving people something they want is hard, and execution/production are hard.