There is a pasuk that says :
"Like a dog who returns to his vomit,
so too a fool returns to his foolishness"
a dog eats something , and then throws it up, then he sniffs and starts to eat it again,
so too a fool does a foolishness, gets disgusted with it, and the goes back and does it again!
a good moshol for us guys who act out ,get disgusted ,and then do it again!
a picture is worth a thousand words I saw a great picture from gye that says it all !