For single bets most often, it's looking forward to getting some more accuracy in your bet than you will get with multiple picks and there's some level of certainty that comes with single bet such that only in a very few cases that it happens to be lost at the end of the day, single games reduce your risk, it also reduce your chances of losses and further gives you an edge at winning more often but then for the ones who don't consider accuracy and all that, accumulated bet is their run to option, personally I chose depending on what I want at the moment, if I want accuracy I chose a single bet or limit my picks to just three otherwise I just do multiple picks.