How does Doctor Strange viewing the future work?

Something that's always bugged me while watching Infinity War is that Strange says he views millions of possible futures and only finds one in which they win against Thanos. So is the number of possible futures infinite or not? Because if there are an infinite number of futures, wouldn't there also be an infinite number of futures where the Avengers win. Or does it not work that way? Or is it just for dramatic effect in the plot? How did you guys interpret it?