My oldest (8.5) had hers done at 1 year. I wanted to do it earlier, my dh wanted to do it much later - mommy wins.

We kept the peircing ear rings in or solid gold sleeper hoops for a while becuase she had sensitivity to almost all of the other ones. By 4 we discovered that she was allergic to nickle and even the 'sensitive ears' earrings that you can get at Claires, Target etc have nickle in them and by that point she was done dealing with her earrings itching and didn't want to try the supposedly nickle free earrings. She kept her solid gold ones in until she was about 5 then took them out one day and decided to not put them back in. Her holes closed up and at 6 when she wanted to wear them again the only choice was to redo it. She didn't want to. Now at 8.5 she's thinking about it again (you can still see her holes, they're just closed) but it's rarely gone beyond pointing out cute earring she couldn't wear anyways due to her allergy. At this point it's her choice.
My younger two are 2 & 3 and I haven't bothered. The middle probably wouldn't bother hers, but the younger would pull on her own as well as sisters, she's pulled mine out as well. Several times in fact, even as a tiny baby. Just different temperements.
I had my first set done when I was about 6 mo. My grandfather nearly disowned my mom! lol I got my second set done at 10. I still have both sets of holes w/o issue and wear earrings whenever the mood strikes me. Oddly enough, I've had my cartlidge peirced 3 times and each time had serious medical issues with it!
I don't think there's a right or wrong answer to it. And the backs on the peircing earrings are really secure, so you don't have to worry about those coming off. You can also buy these really cute earrings that are pearls on one side and the other side is a gold ball that screws on. You can wear them either on the pearl side, or the gold side. My girlfriend sent my daughter a pair for Christmas one year. I think she said they were about $15 at
walmart. As for the pain, it's no worse than immunizations if you immunize, and most places that peirce will do both ears on a baby at the same time. The noise scares them more than the peircing hurts.