Kreskin:
I prefer to go with Aristotle's "People are what they repeatedly do."
If you are kind more often than not, well then you're mostly kind. Same with every other characteristic. Repetition is what shows who we are.
To judge someone by one thing they've done might have some value, like an act of heroism or barbarism; while it might never be repeated in their lifetime, it gives some insight into who they are. But it's the everyday things that I think we are judged by, for the most part. If you are consistently friendly, happy and nice, why wouldn't people think well of you and want to be around you?
If you then did something bad, maybe then it wouldn't be so hard to get back into people's good graces.
Same goes for an average person in a generous. low-stress environment. Since there is nothing at stake, if you did a bad thing, simple contrition might be enough to get back in everybody's good graces.
But what if you live in a competitive environment? Well then, betrayal and mean judgment might abound. The slightest slip and you're an outcast forever.
Sorry I can't give you a simple answer - people and the world we create well - it's all so complicated.
I wouldn't have it any other way.
Pangloss