I'm a huge Harry Potter fan, but it never occurred to me to relate that scene to startups in that way. It makes me smile. :) However, I would tweak the "solid wall" metaphor a bit in the context of startups. For example, running full ahead with a bad idea will never magically become a good idea simply by upping confidence level. I would say the metaphor is more like Book 2 where they hit the wall and bounce back painfully (because Dobby sealed it) but find another way to get to school anyway. I think that's more what startup success looks like. Simply having the confidence to run forward is more about how to look at life in general I'd say, when we talk ourselves out of attempting to do things for reasons which are really nothing but false fears.