We defended two keeps last night (Hlid and Arvakr) with few hibs against many mids, and never got the defence tick, it should have been good as we held them off for a while. Even after several hours neither of them came through.
Same here. I got into Crimm defense. Then more than 2 hours after I did not get any defense tick while the keep was taken and not under attack at all.
It is strange, because I got ticks for all other keeps and towers I fought in.