[logicchains]

Integrity, like any human characteristic, is a distribution; some people have more of it than others. If you just view everybody as the same, you're more likely to end up with somebody with average integrity, as opposed to if you actively searched for people displaying greater integrity. Similarly, assessing people is a skill that varies greatly among people, and if you just take the view that everybody is the same at it, you'll have no motivation to develop that skill yourself.