Thou Shalt Not Attempt to Reanimate Dead Coffee

There’s a guy at work — let’s just call him Bob — yes, Bob, the bastard is at it again — who has a frugal streak in him. While in most circumstances this is fine, as generally speaking less is more, but in this case it is not.
Most definitely not.
Bob is conscientious enough to brew a new pot when he discovers the coffee is gone. Points for Bob! However, Bob’s frugal nature tells him to not remove the old grinds from the coffee pot. No. Instead he adds a couple scoops of fresh grinds right on top of the old ones, and then makes the coffee with that.
Frugal conscientious Bob is attempting to reanimate dead coffee.
No, Bob! No! Bad! Bad Bob!
Thou shalt not attempt to reanimate dead coffee!

Is it truly his frugal nature which prompts him to commit this sin? Or laziness? Or just plain ignorance? Does Bob think that coffee tastes so awful anyway that doing this will make no difference? Or are all the taste buds in Bob’s mouth as dead as the coffee he’s trying to reanimate?
Regardless, what he’s doing is a sin against coffee — and the result is horrid, putrid zombie coffee from Hell.
If you see Bob do this, immediately roll up a newspaper and smack him.
Bob must be stopped!