You've posted in a few unsubstantial threads that have been trashed (some have been posted numerous times as well). And as Welsh already stated you've posted a few times in Serious Discussion which also don't count.
I would add that these are otherwise known as spam megathreads, which are usually in Bitcoin Discussion, Economics, and Altcoin Discussion. If the threads you're posting in have titles that are idiotic questions like "Bitcoin vs. Altcoin", "Trading or investing" or some such, and they run over 50 pages (an arbitrary number picked by myself), those posts are most likely, eventually, going to get deleted--and you won't get any notification about it. The sections I mentioned are breeding grounds for spammers and people farming accounts, and I'd say 90% of threads there are either actual or potential spam megathreads. If you're so concerned about posts being deleted, don't post there. Be more selective about where you're posting, and definitely watch the quality of what you're writing.
If all of that fails, just suck it up and get over it. I just had a few posts deleted by mods, and you don't hear me bitching about it. That's part of life on bitcointalk.
