The advantage of being at the bottom, is that you get to see everyone's soles. Then you'll know who has been wading through mud, who has stepped in blood, etc.
In clearer language, being useless can be a good thing because your friends are all true friends, not friends who just want something out of you.
Ok, that's an over-generalisation. I got pretty disgusted with a "friend" just now, who started chatting with me at the bus stop, and then, while I was in mid-sentence, turned to someone who'd just arrived and started chatting happily with him. And ignored me totally after that. It's not the first time he's done that, either. I should have smacked him.. *growl*