The main problem with football is that the sample sizes for games is WAY too small, and the weather and schedule can be such a huge factor.
Baseball and basketball are sabermetric dream sports because the weather is almost always fairly controlled, the number of games are enough to get into the "long run", and the schedule is pretty consistent from year to year.
NFL football, and fantasy football in general has by far and away the most luck associated with it compared to baseball, basketball, and probably even hockey for that matter.
1 or 2 monster games can affect your end of year statistics so much it's unreal in football.
See Dwayne Bowe being ranked in the top 10-12 WR's?
Dude had like 4-5 insane games last year and a ton of crappy ones. The guy blows. Yet those end of year stats look great and someone's going to bite on him and make a huge error.
It's football's randomness that makes it work though... in baseball or basketball it's surely the guy who spends the most time on it and plays correctly that wins.
Football is more like poker where you can have Aces and still get served by 72 offsuit... and it's that randomness that allows the people not wanting to put the time in, to occasionally win.
Effort still matters - we have a guy in our league who drafts and forgets it... almost never changes his lineup, and most certainly is never going to make a transaction... he's not going to win very often if ever.... but your effort won't matter as much to you in FFL with it's one and done playoff formats compared to other sports.