I guess (and I think it is right) that the account was sold recently and new owner wanted to make a new profile by deleting all old threads.
That's very unlikely: why would anyone buy a Full Member account just to reduce it to Newbie again? Accounts are mainly bought to earn from signature campaigns, reducing the level makes that impossible again.
That leaves the option that the original owner has - for some reason - deleted most of his posts.
I propose Theymos to make a change to the forum system. If someone delete their old posts, their ranks and their merits should decrease too. It's not fair if a Newbie got 100 merits for nothing
It's exactly as (un)fair as the Full Member who originally got the 100 Merits. Nothing changed there.
(particularly if the account was sold and violates the forum rules).
Selling accounts doesn't violate forum rules (but will likely earn you red trust).
I don't think it is that unlikely. The Merit is far more valuable than the activity now. If the post history was particularly poor quality spam or in a language the buyer doesn't speak it might make the fact that it had been sold very obvious. With the post history deleted it is difficult to tell what happened and it'll only take 120 days to get back to Full Member.
