On the other hand, one shouldn't underestimate the power of not knowing something is impossible.
If you talk to a lot of others who have worked in the space you may well end up with a long list of reasons why your idea is doomed. It may stop you from wasting time on an idea that can't succeed. Or, possibly more likely, it will muddy your thoughts and prevent you from observing the space with the fresh eyes that are needed to see what those before you have missed.
But all too often companies just start building without understanding why the previous attempts have failed.
Sometimes you need to just start building to begin to understand exactly why previous attempts have failed.
I'm a big proponent of naively trying to do what others tell me is impossible and it's served me perfectly well. That being said, if someone's startup was unsuccessful for a very clear reason that still exists today, the point is to understand that cause and your own plan for overcoming it, or don't start dedicating a bunch of resources only to get to the exact same point and realize it's not something that can be overcome.
It would be like starting a poker website now and completely ignoring what just happened to Full Tilt. Online poker is illegal. Until that changes, probably not a good space to play in.
If you talk to a lot of others who have worked in the space you may well end up with a long list of reasons why your idea is doomed. It may stop you from wasting time on an idea that can't succeed. Or, possibly more likely, it will muddy your thoughts and prevent you from observing the space with the fresh eyes that are needed to see what those before you have missed.
But all too often companies just start building without understanding why the previous attempts have failed.
Sometimes you need to just start building to begin to understand exactly why previous attempts have failed.