Like the title says: Why do some profiles not have a "Last Activity" stamp?

Some have it on the right side of their profile page, and it lists the last date/time the person was on the site. Others have nothing there. Why is that? Is it something I can fix on my end?

I'm wondering because sometimes I want to check and see if someone is still around, either because I have a question for them, or I am curious to see if they are still maintaining (not that they can't be if they're not on this site), etc., etc.

Thanks!

I'm unsure (I wasn't even aware users had the ability to see that). I would say that if you have seen them post recently, then they are probably around. Also, you might get responses from other people that you aren't aware of if you post in a thread.

It could also be that users have the choice to show or hide that information when they set up their profile. I would also check see other posts to see if they are still posting, but they could be reading and not posting.

Your profile options allow you to choose to be 'invisible'. This will hide when you are currently online, as well as your last date of activity.

You can also send them a "private message" if you want to check on them.