Life Steal

The life steal stat in Neverwinter has long been my go-to example of why allowing too much self-healing is bad, at least in a game that's supposed to have a trinity system. People were healing themselves so much that dedicated healers quickly became redundant, and since it scaled with damage output, characters also became increasingly unkillable the more damage they did.

It received a big nerf at least once (possibly more often than that) but it was only with Undermountain that Cryptic decided to remove the stat altogether, while also all but eliminating abilities that used to do both damage and healing simultaneously.

And I've got to say, even though I agree that it was bad... suddenly being without it after years of playing a certain way sucks too, as my characters now have to consume potions/health stones like nobody's business. Considering that regular potions barely heal you at all and the actually useful health stones are sold in the cash shop, it's also hard not to suspect Cryptic of having made this move to encourage cash shop purchases rather than out of any actual gameplay concerns.