Adult males who stop smoking have improved sexual acts.

This might be enough to get some people to quit. A study has found that men who quit smoking had improved erections and reached 
maximal arousal 5 times faster than smokers who relapsed. 
Researchers recruited 65 men who were quitting using nicotine patches (and no other drugs) and they were willing to be… measured in a lab a few times. They found that men who had successfully quit improved their sexual performance. Interestingly, the men reported no subjective improvement in their own ratings of sexual functioning.