Betting on a single sport lets you focus all your time and energy in mastering everything about it. Although betting on multiple sports gives you a lot of chances to win, it also means there’s a greater possibility of losing more.
The importance of betting on one sport gives you time to learn everything about it. If you can’t consistently win on one, why would betting on multiple sports be any different?
There’s nothing wrong with betting on multiple sports as long as you’re willing to commit and do the same load of work on other sports while keeping your edge on the first.