It depends on the circumstances, but I'd say ultimately everyone deserves a second chance if they're prepared to acknowledge the fact they made a mistake and are working towards fixing whatever it is they did.

In your situation if you've bullied someone the only way you'd get a second chance is to actually apologise to the person you've bullied and make an effort to try and change the way you treat people, putting more thought into how your words or actions might affect other people.

Everyone deserves a second chance as long as they truely and honestly want to/have changed. And I mean everyone. It doesn't mean there shouldn't be repercussions for their actions, and it doesn't mean that everyone they've wronged has to or is going to forgive them, but everyone deserves that chance.

Well, I apologized to him and we're friends now.