One of the biggest reasons so many people love March Madness is that we love to root for underdogs.
Underdogs win with surprising frequency in the tournament. It's well-known that, in the first round, No. 12 seeds often beat No. 5 seeds (about 41 percent of the time since 1995). But other low-seeded underdogs win regularly, too — far more often than underdogs win in the NBA playoffs.
This isn't an accident. As this video shows, there are all sorts of features built into the NCAA tournament that tilt the playing field toward underdogs.
Teams advance by winning single games, not series
The simple fact that teams only play each other once — instead of playing best-of-seven series, like in the NBA — makes a huge difference. Underdog teams that would have no chance of beating favorites four times out of seven have a much better shot of beating them just once.
Games are shorter, with a longer shot clock
NCAA games are only 40 minutes (rather than the NBA's 48) and feature a longer shot clock (35 seconds, instead of 24), allowing teams to take up more time with each possession.
This means if an underdog team takes its time on offense, it can cut down on the number of possessions in a game that's shorter to begin with. So there's less of a sample size to determine which team is better — and more of a chance for underdogs to end up winning, even if they would have lost a longer game.
Games are played on neutral courts
This isn't always strictly true (many high seeds get to play on courts pretty close to their campuses in the early rounds, and they bring a lot of fans) but in general, most March Madness games are played on neutral courts. And many of the fans present who don't have a rooting interest in the game will cheer for the underdog — either because they simply want to see an upset, or because the winner of the game will face their own team, and they assume their team will have a better chance against the underdog.
As a result, March Madness favorites don't enjoy the same home-court advantage they get in the NBA playoffs, where they always get to play the decisive game seven at home. Underdogs often have the crowd behind them instead.