"No man knows how bad he is until he has tried very hard to be good."
"A silly idea is current that good people do not know what temptation mean. This is an obvious lie. Only those who try to resist temptation know how strong it is. After all, you find out the strength of the German army by fighting against it, not by giving in. You find out the strength of the wind by trying to talk against it, but not by lying down. A man who gives into temptation after 5 minutes simply does not know what it would have been like an hour later. That is why bad people, in one sense, know very little about badness. They have lived a sheltered life by always giving in.
"We never find out the strength of the evil impulse inside us until we try to fight it: and Christ, because he was the only man who never yielded to temptation, is also the only man who knows to the full what temptation means -- the only complete realist."
-C.S. Lewis, Mere Christianity
It follows, I think, the worse you think you are doing, the more you are trying. Sometimes I get terribly discouraged about my personality traits and weaknesses and disparage any and all progress and good I've made. To try hard is to feel more deeply the impact of the fall.