I registered on superuser.com and posted a couple of answers under the account: https://superuser.com/users/8954/lazlow
However, today I visited the site again - having not logged in for a few months (maybe longer) and found that the page no longer existed. After logging in with my Google OpenID (same as used on StackOverflow/ServerFault) I was given the option to setup a new account as normal, which resulted in: https://superuser.com/users/96197/lazlow
My question is - have very old/inactive accounts been deleted from the site? It's not too much of a problem, as I hadn't accumulated much in the way of reputation - but I'm intrigued to know why accounts need to be deleted.