There was a myth when I was starting out in software that it was possible to write a business plan and have that be what you actually end up doing. You'd plot out a series of steps, and put each one on a numbered slide. Around slide 8 or 9 was one called Exit, where you showed your potential investors how they were going to get rich. Everyone understood that these slides were lies, but you had to act like you believed them. In a way they were buying your ability to bullshit, and everyone knew it.
Even though I never raised VC, I did manage to get a bit of money from angels, launched a company, and zigged and zagged through growth and setbacks, tried one idea out then another, until finally we hit on a winner, bet heavy on it, got lucky and sold out. Our investors did get rich. But the way they got rich had nothing to do with what we told them when we were starting out.
Some days VCs will tell you they invest in ideas, other days they say they invest in people. I was told a few months ago by a young VC, with a straight face, that your idea pretty much has to be a bullseye for something they've already decided they want to do. A few weeks earlier a partner at the same firm told me that they invest in people, and don't give a shit about the idea. Neither is true. Or both. I have no clue.
Whatever investors say, the truth is you win by having a great vision and have the right personal qualities to make it win. Intelligence, drive, curiosity, flexibility, salesmanship, doggedness, all are important qualities. You have to care that people like you, but at the same time, you'll piss a lot of people off, and that can't stop you. Most important, you have to be unable to visualize failure. There's a lot of bullshit floating around these days how failure is good. It's not good. If you're the kind of person who people should invest in, failure should not be a possibility. Even if they fire you, you won't leave. Even if there's no money, you won't quit. If you have to go to board meetings alone, so be it. You. Will. Not. Fail.
But that said, you cannot proceed as if your plan is sacred, because every step you take will teach you so much, that will be what your next moves are based on. Winning is the goal, not realizing your plan. And winning is not a linear thing. You should see your product as a cloud of ideas. Put down a marker in one place, ship it, see how the people respond to it. If that doesn't work, put a marker somewhere else, but still close to your idea, ship, listen. If that works, continue to invest there. Keep putting down bets until one hits.
To do this you have to have good intuition about the product, which means you yourself must be a constant, dependent user of the product. Programmers who think they understand users but are not one themselves are worthless. CEOs are even worse. I was told once by the CEO of a company I was working for that he's a market of one, and his opinion of the product didn't mean a thing. Even though I was very young I knew this was wrong. A year later the company, which was a market leader in its class, was gone.
Most important do not see your progress as a line. It's not. Linear thinking may be good in Dilbert-like companies, where sticking your neck out is a good way to get your head chopped off. But if you're navigating a competitive market filled with unknowns you can't plot a fixed line through that kind of fog. You have to feel your way through it, and in order to do that you have to have a feel for the product, its users, and where the value is.