You gotta look both at odds and also at returns... You bet on (a) and (b) because nobody else has pulled it off so if you can do it, you can win big, and you a

You gotta look both at odds and also at returns... You bet on (a) and (b) because nobody else has pulled it off so if you can do it, you can win big, and you aren't just one of many players in a crowded sea. (c) is a rough bet since you're already huge but you still have a lot of competition and it's a crowded market and you haven't always made as much money per user as people would like...