They didn't win their division...

[SWC75]

But they made it to the World Series:

The 1997 Florida Marlins, (who won the series)
The 2000 New York Mets
The 2002 San Francisco Giants and Anaheim Angels (who won)
The 2003 Florida Marlins, (who won)
The 2004 Boston Red Sox, (who won)
The 2005 Houston Astros
The 2006 Detroit Tigers
The 2007 Colorado Rockies
The 2011 St. Louis Cardinals, (who won)
The 2014 Kansas City Royals and San Francisco Giants, (one of whom will win)

That's a dozen wild card teams of the 40 World Series teams since the current format started, including 6 of the 20 winners.

I decided to compare this to other sports over the same period.

The NBA has had seven "wild card" teams make their final series,: The 99 Knicks, the 02 Lakers, the 0-3 Pistons, the 06 Mavericks, the 07 Spurs and Cavaliers and the 11 Mavericks. The 02 Lakers, the 03 Pistons the 07 Spurs and the 11 Mavericks, (4 teams) won.

The NHL has had 18 "wild cards" playing in the Stanley Cup Finals: Florida in '96, bothe the Red Wings and Flyers in '97, and the Red Wings and Capitals in '98, the Sabres in '99, the Devils in 2000, Anaheim in 03, Calgary '04, Edmonton '05, Ottawa '06, the Penquins in '09, the Flyers in '10, the Kings and devils in '12, the Bruins in '13 and the Kings and Rangers last season. The 97-98 Red Wings, the 00 Devils, the 09 penguins and the 12 and 14 Kings won, (6 winners).

The NFL has had only 6 wild cards: the '97 Broncos, the '99 Titans, the 2000 ravens, the 05 Steelers, (who actually wound up tired for the division title but were relegated to a wild card by tie-breakers), the 07 Giants and the 10 Packers. Ironically, all of those teams won the Super Bwol except the Titans, who came up a yard short.

I had a theory that the more physical the sport, the less likely a "Cinderella" could make the final or win the title. That would explain the NFL but what about the NHL? I also had a theory that baseball would be the easiest sport for a wild card to do well because of it's lack of "physicality" and because of the batting order and the pitching rotation, which prevents stars from dominating play as they could in other sports. Baseball had more wild cards do well than the NBA or the NFL but again, how do you explain the NHL.

I'm still very old fashioned on this subject. I think that if a team spent all the regular season trying to win it's division and succeeded, they should be playing for the title, not the also-rans. If I had the power, (and my power indicator is on "E"), I'd rearrange every sport into four geographical divisions and just have the champions play. or, if you prefer, eight divisions, (which the NFL already has). Winning a division should mean something.

 

[BuffOrange]

It's pretty simple really. When people make fun of March Madness and its randomness, they fail to understand that the NBA is the outlier, not college hoops. Hockey is a ridiculously high variance sport and the players know as much - "yeah ya know, just trying to get traffic in front of the net and get a lucky bounce". Series' that end in 5 games are sometimes very literally three bounces away from ending 4-1 the other way (in fact this actually happened in Buffalo-Ottawa series's in consecutive years, with the series winner winning two OT games each). Plus home ice means jack squat. Baseball is kinda the same way: fluke bloop singles vs well hit line drive double play balls, etc.

With the NFL it's hard to say but a theory I heard from 'Football Outsiders' Aaron Schatz makes sense. The frequent playoff upsets in recent years could just be random, just as the lack of upsets in the '90's were. The reason for this making sense being that empirical data based on regular season records do not support the popular theory that there is more parity now.
If you drew a random card out of a fresh deck 100 times, you can go thru stretches of drawing a numerical card more often than expected (70%/favorite) or a face card more than expected (30%/underdog). But because this is sports everyone has to have a football-related theory about it.
When averaged together there's been about as many playoff upsets as there "should've been" since 1990...so maybe the next few years will be "normal" - with bye week teams in the SB and a couple upsets sprinkled in the playoffs. Maybe that started last year.