Users are not psychic, communication is vital.
It is also more work for the moderators, and can provoke private arguments when none would have ordinarily happened.
At the end of the day, if someone writes something bad enough for a moderator to warrant deleting it for the good of the board, then, well, I think it should just be deleted, and the owner only informed if the moderator wishes to take it further and spend the time explaining. So long as the stated policy of the forum is to assume if your posts vanishes, then it's been deleted by a moderator, and if you didn't get a reason and want one, then you can ask.
IME, most people do not bother asking, they know what they said risked being deleted.
Remember, at the end of the day,
very few posts get deleted on this forum. I'm talking maybe one in 1000 at best. With 700+ posts day on here, post deletions