Dilbert, Season 1

PHB:
Well, there's no point in killing a dead horse.

Dilbert:
You mean there's no point in beating a dead horse.

PHB:
Why would anyone beat a dead horse?

Dilbert:
Why would anyone kill a dead horse?

PHB:
Maybe it kicked ya.

Dilbert:
It's dead!

PHB:
And so is every customer who has used our flagship product!