They could probably refine them but taking them out would mean having to make new ones from scratch which is more money and stuff they have do. Which ones specifically do you mean?
Duuude, only the ones from DOA1 and DOA2. The ones that are new in DOA3 still have a place because they still look "new", but the ones from DOA2 and before need some change.
So we just gonna get to changing the animations of Jann Lee's jabs because they're old xD. There are some animations that need change but I don't think because of them being old is the reason bro xD
What else would you want to think of a reason why animations need to change aside from being old without offending more people who take pride with DOA's animations?
Some animations frame-for-frame deadass just look weird, therefore they'd need changing for those reasons. Especially if they don't want people going "what the fuck" in photo mode xD