Do we take selfies because no one else wants to take our picture?

that might be why

I think there are ultimately lots of reasons! Selfies are great because we know our angles ;) We know how to take more flattering photos of ourself than having someone else do it. I think selfies are also a great way to appreciate our own beauty or learn to love it. Sometimes it's for mere documentation purposes - to remember ourselves at a certain point in life. And yes, probably sometimes because there isn't anyone else to do it for us.