The soft cap removes all dodges from the enemy. That's required for most of the melee DPS since mobs can dodge from behind. That's why melee should stay behind of the mob all the time.
Originally Posted by Whitegold
The hard cap is for parry. Mobs can't parry from behind but they can from front. It's the reason why melee DPS won't bother taking more expertise than the soft cap. But it's highly valuable for a tank because they're in front of the mob all the time.
-Edit- Forgot that add that when creatures parry your attack, their swing timer for the next swing is reduced which means that expertise also works as a mitigation stat.
Originally Posted by Blizzard
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