I've also noticed American sports take longer to develop.
Nascar, is only exciting the last 10 laps where everyone goes all out
Basketbal, Is only exciting in the last minutes with desperation shots going off
Handegg, Is only exciting in the last quarter, or when a big play happens
Baseball, only exciting last inning
etc.
Where as football is always a chance for something to happen, but happens less often.
American sports are more about patiently waiting for a game to unfold, where as rugby and football, stuff happens non-stop.