"What do a hundred failures matter, when one success can change the world ?"
This is sort of an ambiguous statment. (or reversible or something)
You could easily argue. (if your a pessimist)
"What do a hundred successes matter, when one failure can change the world?"
But I think the point he is making is that you can't do something unless you try.
"If at first you don't succeed, try and try again"