The sweet spot is right down the middle, and is extremely rare.
This is a pat phrase that means nothing. If you assume there are extremes on either side of a desired trait you can say it's in the middle, but it's not a useful criteria.
PS: What you really want is someone who is more innovative than 95% of people out there, but still capable of functioning within the context of a company.
The right amount of two distinct traits within an individual does in no way imply anything about where the medium distribution of those two traits exists within the general population.
You do want someone who processes both conformist tendencies and initiative in about equal percentage share. Yes, that is unlike a vast majority of people.
This is a pat phrase that means nothing. If you assume there are extremes on either side of a desired trait you can say it's in the middle, but it's not a useful criteria.
PS: What you really want is someone who is more innovative than 95% of people out there, but still capable of functioning within the context of a company.