Sports Illustrated has predicted that the Cleveland Indians will win the 2015 World Series. Billy Beane, the remarkably successful general manager of the Oakland Athletics, has famously said that the playoffs are a crapshoot. How do these tidbits work together? Well, as SI points out and Beane's remark essentially confirms, the best teams in the regular season don't necessarily win the World Series (or by extension, the Super Bowl or Stanley Cup and so on). Just getting into the postseason is all a team needs in order to have the chance at finishing on top of the heap. SI notes that both World Series participants, the Giants and the Royals, were wild cards in the 2014 playoffs.
This means simply that playoffs aren't fair to the better teams. At the highest levels of play anyone can beat anyone else in a short series, especially as overall weaker teams can shorten their benches. It isn't unusual in baseball for example to see a fifth starter relegated to the bullpen to strengthen it for a short run. But over the course of a full season a team can't do that. It must play its whole team. This is what allows the cream to rise: weaknesses of whole teams tend to get exposed over time. These weaknesses can be hidden in short term events such as playoffs.
On another front, the effect of mere hot streaks, momentum, are generally ameliorated during the regular season. One might win several games in a row, even 10 or 12, but that by itself won't power a team into the playoffs. Such a run in the postseason, even a lesser run such as 11-3 (which would win a baseball World Series) can win championships. By rights, then, they ought to be dismissed as merely lucky when scored against superior opponents.
If sports are supposed to be about fairness and the best team winning, if they are supposed to instruct both participants and the broader society in good sportsmanship and in recognizing and accepting that competition means separating the wheat from the chaff and that there should be no jealousy among us in accepting that, then they need to reassess the idea of playoffs. As Sparky Anderson said, the best team in baseball is the team with the best regular season record and not necessarily the World Series winner.
Playoffs hinder rather than build character and mettle. It's the long haul which creates those virtues in a person. If sports wish to teach society that, they need to instill them within their systems of play. Anything less, and less is what we've got now, is nothing more than bilking people out of their cash with an artificial excitement. Such bread and circuses will only make a nation soft. Both our athletics and ourselves will be weakened.