Why are athletes superstitious and is it actually helpful?

"I believe in the sausage," said pitcher Kody Funderburk while smiling. "We keep touching the sausage in the dugout," quipped third baseman Kyle Farmer. A summer sausage, still wrapped in plastic, is apparently what's propelled the Twins to 12 straight victories. "I think we're just creatures of habit," said first baseman Alex Kirilloff when asked why athletes are superstituous.