There have been people in my past that wanted to start a project that I didn't think they were capable of finishing, because either it was too large, they didn't have the skills/smarts (not that I thought they were stupid, just that I thought it would take exceptional intelligence), or both. A few of them succeeded, either in the original task, or the effort and journey was well worth the price paid.

Part of this was hubris. The thought of someone I considered less capable than myself accomplishing something I felt I could not damaged my ego. This was humbling.

Part of this was experience. The experience to know that attempting the hard or impossible is sometimes worth the effort, whether you succeed or not. This was educational.

Part of this was ambition. Ambition to do something new, to ignore the naysayers and noways when needed, and forge your own path, which I've always felt short on, but have steadily worked on over time. This is ongoing.