So you see, if I may be indulged in a little self-congratulatory chat, the real key to Earnest Ragging (TM) is not the hectoring, the castigation and denigration, but rather the conjunction of the sour complaints with on the other hand, praise, reward (in the form of putting players high on your personal prospect ranking, say), letting the player know you believe in them and see a greater performance in the future, while beating them mercilessly with your snark stick. It can't be done clumsily. There's an art to it.
Ooh! Majestic! Nicely done, Aramis. Now you just keep on being hot and try not to be terrible anymore!