I remember being very impressed once watching HHH sell after the end of his match. So many guys stop selling as soon as the bell rings, which kind of kills the performance. If you just had your leg, arm, back, etc. severely worked over for half of a match, why would you suddenly be "healed" after rolling out of the ring?
Hunter had just had his leg worked over for about the last ten minutes of the match. He sold it beautifully as he exited the ring and limped all the way up the ramp until he was behind the curtain.
THAT is good selling.