All of those are true, but there's another important reason I think is worth adding: the only way go get truly better at something is to do it over and over aga

All of those are true, but there's another important reason I think is worth adding: the only way go get truly better at something is to do it over and over again, and most technically adapt people have a long string of side projects, experiments, etc. A lot of them are not great, but the act of attempting to create them and seeing them in real life gradually helps one to have a practiced feeling about what ideas are worth pursuing and what ideas are not worth pursuing. If someone has never gone though that idea->attempted implementation->post mortem loop, it's very likely that they haven't developed a good muscle for coming up with good ideas. They just sit around babying whatever idea is currently in their head, never really challenging it. (for what it's worth, this idea is something I first encountered in one of interviews in Founders at Work - I just really like the idea)