When did "screwing up" become acceptable?

I'm seeing this in all sorts of groups I've been part of: bands, running clubs, etc... where people freely admit they've made mistakes, their friends tell them "it's okay", and life goes on. For instance, I was being driven bananas at a band rehearsal recently, when we had to keep on replaying the same section of a song over and over again due to someone's constant "I lost my place in the music again," said with a coy smile. Why the hell is that okay? And various running clubs I've been part of: the same people will come back week after week confessing that they hadn't run in two weeks and they'd been "bad". Am I supposed to validate your existence every single time?

So I'm not your cop. I'm not the police of your life. But sometimes, these situations affect others -- namely me. I'm focused enough on my music to know where we are -- or at least only lose my place once, learn from that, and keep focused. And if I set running goals that require more than once-weekly running, I'll stick to it and entirely eat the blame if something goes wrong.

But society accepts the "I screwed up; am I still OK?" method far too easily these days. I don't get it. Perhaps it ties in to the Catholic confessional idea, where people go to confessional, say "I'm sorry, I slept with twelve different men this week" and they're told "20 Hail Marys, and don't do it again." What do you bet this same person comes back the following week, saying "well... I tried, but I still slept with 11 men this week"? What kind of punishment has the person received? Not to get into a religious argument over how accepting God is or isn't of sinners, but this takes things to the extreme.

So as things go, if you confess your sins, you're absolved, and life goes on. It just annoys the hell out of me. Why was I raised to be so responsible... life would be so much easier otherwise.