I'm on POF. I don't have a profile picture, as I look like a right numpty in photos. In fact, when I shuffle off this mortal planet, those, who clear out my home will have no idea what I look like. There is a picture taken, with my parents, for their Ruby Wedding Anniversary. It's not on show.
The other reason I don't have a profile picture, is that I have alopecia and wear a hairpiece, that looks like a hairpiece in photos. I don't think that people, on POF, will understand my reluctance to have a photo. Also, I think I look ugly. I need to lose weight, which I'm doing gradually.
Ergo, by not having a profile picture, on POF, I'm not putting off people, before they get to meet me. I want them to get to know me, through messages/phone calls, etc. And when they meet me, they will see the ghastly vision that is me.