Sometimes my brain doesn't take care of its flesh vehicle for a while; typical situation is I don't get a shower or shave for a little too long. And then my brain becomes convinced that it doesn't like itself very much. Then another part of my brain realizes what's going on, but has learned that my brain isn't very reliable, and is also fairly open to suggestion. So my brain takes a shower and shaves and puts on clean clothes, and then my brain is tricked into liking itself again.

It's literally like playing peekaboo with your own self-esteem in the mirror.