"So, on the one hand a certain openness and teachability is necessary, but then at strategic points in the development of an idea, a certain stubbornness and myopia seems to be equally important to the ultimate execution of a vision."

I think that's the reason why I don't seem to be able to commit myself to one thing.

But is it mostly a personal trait and forcing yourself just can't work? How should it be possible to switch between openness and stubbornness on demand?

Perhaps that's the reason why there are different personal traits, because switching doesn't work, so it's easier to get the balance by different personal traits, arguing against each other.

There might be personalities, which are able to balance themself better, but I don't seem to be one of them.