I would normally agree with a comment like the one space guy mentioned, this is a rather bigger problem than believed. My wife and I both have the Galaxy S3, both were charging great, usually 100% within 2 hours. After she received the Jelly Bean update, (mine has yet to come through) her phone began to take a long time to charge. We changed chargers since mine was charging fine and she still had the same problem. Mine charges fine with any charger. We swapped batteries. I can charge fully with her old battery and it holds great. The problem is her phone and it has nothing to do with 'being patient'. I've been searching for quite a while about this and no real solution yet. Everything seems to point to the Jelly Bean update. Anyhow, although I don't have a solution, I wanted to let you know that you are not alone and it's extremely frustrating. The phone should charge a lot faster and I have just proved it has nothing to do with 'being patient'.
My two cents.