Well, I don't have an explanation on this matter. But, As far as I remember, Not only this, but I did this a few more times without knowing the rules (As I have already said that those few weeks were my newbie days).
I was asked to respond to naim027's plagiarism, so I'll just add my 2 sats

I've said it before: plagiarism is "normal" on the internet, and Bitcointalk is the rare exception. Barely anyone ever reads the rules when they first join a forum, so plagiarism is likely to happen. In naim027's case, his account was already 4 years old when this plagiarism happened, but he
barely posted during those first years.
I always assumed Bitcointalk is so strict because of people spamming for their post count. I can't really tell if that was the case here, but some Newbies post in WO to earn Merit so it could have been the case.
Since naim027 edited his plagiarism before being (signature) banned, I don't expect him to be banned now. It might be a good moment for him to go over all his old posts before someone else does.