"So, doctor, why is my weiner so sore?"
"How often do you masturbate, Tommy?"
"Hm, around 4-6 times?"
"Ok, well, 4-6 times per week is not so unusual for a young man of your age?"
"Per week?!? I thought, you meant per day!"
"Ohhhhh.... Now that explains a lot. I'll recommend a better lube!"