Question about clicking on a profile

A few minutes ago, from the main forums page, I accidentally clicked on the name of the last poster, instead of the thread title. The profile of a completely different poster came up. I clicked on the names of the rest of the last-posters in each forum, and their own profile came up- the first one was the only one that was different. In that particular forum, clicking on that particular poster’s name led to his own profile.

So why, from the main forums page, does clicking on this poster’s name bring up someone else’s profile?
Just curious (and yes, bored).

The link for the last poster is not explicitly associated with the actual poster’s profile, but rather takes the form:

http://boards.straightdope.com/sdmb/member.php?find=lastposter

If someone else posted to the forum or thread in question before you managed to click the link, you’ll get their profile instead.

Ah, but of course. Curiosity sated but boredom persists.

Thanks.