We have a tendency to remember the good and not the bad, and we want to see our friends do well. Someone else also pointed out here in the comments that no one

We have a tendency to remember the good and not the bad, and we want to see our friends do well. Someone else also pointed out here in the comments that no one wants to publicly state they made a bad call if they can avoid it because it will likely damage them personally. We give others lots of chances, or we encourage and cheer them when others are taking chances on them in the hopes that they'll do better this time even when we would no longer risk our own skin. I imagine most of us think, "S/he was so close to success. Maybe s/he'll have learned! What could be the harm in talking them up a bit? Besides, no one wants to ruin someone else's life,"