That can't be true. The best pitchers in the league usually win the most games because they give their team a better chance to win the game. I believe there is a big difference between winning 20 games and winning 15. Plus, w/l percentage means something too. Now, a pitcher can't control run support, but they do control how often they go deep enough into games to get a decision. I think there is something to be said for starting pitchers that have good winning percentages. A bad pitcher won't win 2x more games than he losses, but a bad pitcher could be over .500. That is the problem, you have to have perspective with the stat. Looking at wins, Gibson and Cosart both have 13 wins, 11 losses and 10 losses respectively. Cosart has a few more strikeouts. Pretty similar pitchers. Gibson's ERA is 4.5, Cosart's is 3.7. Gibson did allow a few more hits, but walked less. Pretty similar pitchers, with the outling statistic being ERA.