A man goes to a doctor.  He complains about his genitals having a red rash.  His doctor says:
 "I think I found your problem.  You have to stop masturbating for your rash to go away."
 "But doctor, I can't!  I constantly feel the urge to keep doing it."
 "You need to learn to control it."
 "I thought masturbation was mostly harmless."
 "It is.  But if you don't stop masturbating, I can't examine your rash."