My son was like yours too. But then I started fining him for dishes that he left around - 50 cents a dish. Each meal cost him about $2.00 so after just one week he figured it was worth his time to start cleaning up. It's been great!

I had a similar experience- only when I punished my messy daughter did she finally start cleaning up. Her punishment was if I found plates around I would wash them and she would lose computer for that night. Since she's pretty addicted to her computer time, this "cured" her within one day (she lost computer one time and then made sure to never lose it again).

These parents are all using the 2X-Rule - making a predictable consequence for an unacceptable behavior. When used only rarely, the 2X-Rule is a very effective, healthy way of setting boundaries. Your son is a real nice guy apparently but he doesn't take you seriously. If he starts to lose his allowance, his car keys, his cell phone or his computer access he will realize that his game is over - he has to start performing. Pick one consequence. See how he responds. If after 3 times of applying the consequence he is still leaving a mess, drop that consequence and use a different one. Try that for 3 times and see how it goes. Keep dropping them if they don't change his behavior. Eventually you'll find his "Achilles heel" - the sensitive spot that makes him say "ouch!"  Then you'll finally have a clean kitchen.  Good luck.  Sarah Chana