Why do people "retire" on PC?

Why do many people choose to do this instead of simply leave the forum [whether it's temporary/permanent]?
I've seen some really insightful and active posters retire and, as a result, I'm kind of confused..

In theory it seems simple enough but in practice some people just don't have the willpower to restrain themselves to not log onto PerC.

PerC is such a huge distraction when comes to exam/studying time.
For me, it's kinda addictive that I almost feel obligated to read every single post.
Sometimes I go to bed late at night just because of reading/answering the threads.

I dunno, but when one of my favorite members, susurration/Nova left rather abruptly, it made me sad. It also made me think about my own retirement someday...

Old age, duh.

Well, I wasn't addicted or anything when I retired. It can be a distraction, but I am sure people retire for reasons besides excessive Perc activity. I retired ( was away for over 6 months) because I was traveling to areas where I'd have limited internet access. I also wanted to get away from the whole techno centric lifestyle thing.

Right now, I don't feel inclined to participate much. I will also be returning to school, in future. So, there's a good chance I will retire my account for an extended period at some point.

Some people are able to extract all they can from the forum and move on. Some get busier, go through important life changes. It's also good to retire instead of just becoming inactive so that your contacts know that you aren't responding to their posts/PMs etc. because you are no longer around.

P.S. I was away when @susurration retired. I never got to interact with her, but I really enjoyed reading her posts. I miss interacting with @etherealuntouaswithin and some others who have retired. I just wish them all the best with their lives. It was nice getting to know them while they were around.

I suppose the answers will be as individual as the people that leave, and the greatest frustration about it is precisely that we will never know. I don't ever plan to retire. It's too final. I might become indefinitely inactive, but I prefer to operate on a philosophy of 'never say never'. Must be the P in me. That said, I also miss susurration's input...

To me it isn't so much about lack of willpower, but finalizing the decision to some extent and leaving an indicator that the account is not active. It also makes it a bit less frivolous and gives you pause to think about it. I've seen forums where people announce that they are going to 'leave' every other day (and they come back every other day) so if nothing else, retirement is a built in way to mitigate this behavior.

I don't even know how to retire :(). Can't seem to find any setting for it.

I was almost positive it was the retiring gnomes that went to and fro making people retire.