Do you think someone must have something wrong with them if they seem to go through a lot of friends?

There are some people who wants to be friends with everyone and there are those who only wants to have a few close friends.

If they go through a lot of friends it seems they are either very picky about the ones they choose to keep or yes, the other people don't care for them much.

depends on what going through a lot of friends means. if it means offending old friends and finding new ones, i think there is something wrong. If it's having 50 high school friends and not speaking to them again now that you're 40, i think that's normal.