What Motivates People to Make Their Aol or Yahoo Profiles Private?

im aware that its their profile and they can do with it whatever they want. and i can understand that no sane person is going to put things like their address or phone number out there. however, when i see someone who has a problem filling out a basic profile giving truthful insight into the persons interests and personality, something is definitely not kosher here. and, when a major life change, like getting married takes place, and they suddenly switch to private, something is very wrong here.
i would be the first to let others know im married.

Suggestion:

Well I don't think the majority of people on here are here to make internet friends, just help people with questions. I personally had a stalker that caused me to make my profile private. She evidently didn't like the way I answered her "hair coloring" question & actually wrote a bunch of nonsense on her own profile about me! And would go & do a bunch of childish things like put thumbs down on all my answers (when it wasn't private) & go & answer all the questions I had with snide remarks & comments to me. The only thing I could do to get rid of her was make my profile private.