It's one thing to remember that we could be wrong.
It's another to remember that we don't know the whole story.
But it's also important to remember who's doing the seeing. I believe it to be true that what we see in other people is what we have in ourselves. We can't recognise qualities that we don't possess, but we can spot (for example) selfishness because we know it only too well.
What parts of ourselves do we find in others, and how should we deal with them?
If it's ours to deal with them at all.