Some of us were never visible online as soon as we became aware of the feature and how to use it.

Takes all kinds I guess.

I happen to be more of the lurking kind and not often up to interactions with ppl who happen to see me as online.........I took care of that by changing my profile to not list me as online.

In my personal experience a few ppl seemed to be upset when I couldn't drop everything and give my attention to them. When they wouldn't or couldn't hear my words saying that I was setting a boundary I then went ahead and turned off most avenues of contact as I do not need that type of interruption and attitude from anyone.

Safety for my own use of these boards as well as protecting my energies.

That's my reason.