Whut? If you're talking about Warrior specifically, Berserk gives Pacify, why does it make sense? Because it boosts your Damage by quite a lot. Theres a downside to using it, it's a trade off. if you dont want pacify, then they'd probably weaken berserk.

If you're talking about pacify even if you havnt used berserk, it could be certain mob actions? your post is hard to tell what you're talking about