I also think it's super important to make something you can sell in addition to making something people want. Frankly, there are so many things people want but not every founder has resources or is well-equipped to sell it.
Your goal as a founder is to maximize chances of __your__ success. Having the right founder-market fit goes a long way.
Definitely agree. It's easy to think of a cool "new social sharing blah" idea -- but guess what? If you're a new founder, without a large persuasive network to get word out to free users -- you're going to have a very hard time.
On the other hand, if you build something useful, and can start racking up subscriptions by doing some footwork (talking to users, giving out free accounts, etc), then you've got a much better chance.
Your goal as a founder is to maximize chances of __your__ success. Having the right founder-market fit goes a long way.