Sounds like manic depression to me.
The example of refining the search for a good candidate is wise though - but it can be explained less dramatically. No candidate was remarkable, though some were good, and he re-advertised the position.
Seeing everything as 'no' or an enthusiastic yes. It's like always being either really down or hyperactively enthusiastic. As others have commented, there are times when something is just 'ok' and still worth doing - or things you just aquiesce to doing that turn out to be really great. I wouldn't want to miss out on such things by only ever (or even mostly) being 'no' or 'hell yeah!'.
The point is that it is worse to miss out on "hell yeah" because you're doing "ok" than it is to miss out on "ok" by doing "hell yeah", and all else being equal your feelings of anticipation are the best indicator that you have of whether something will turn out to be great or not.
Ok that does make sense. But surely the best path is to have a more nuanced evaluation of the options than a binary 'Yay!' or 'no'.
Anyhoo - if someone finds the OP useful then all is well, and maybe someone will.