Casual basketball fans often claim that there’s little reason to watch the NBA before Christmas, or even before the NFL season ends. This is one call in a chorus of complaints that the NBA season is simply too long.

It may be, but the idea that the early part of the season is irrelevant is just wrong. While it’s just Nov. 28, the contours of the NBA playoff picture are already being shaped.

The standings suggest that in the East, 10 teams will battle for eight playoff spots while 11 teams are in the chase in the West. The other nine NBA teams are all at least five games under .500, and all of them are more than two games out of the No. 8 seed.

It is indeed early, but history suggests few teams will rise from the muck even at this stage to sneak into the playoffs.

For example, last season all the eventual playoff teams in the East were .500 or better by the end of November. There was a clear stratification as of Dec. 1, with 10 teams at .500 or above and five teams below water. None of those bottom five teams made the postseason.

In the West, there was less parity: only seven teams were .500 or better on Dec. 1. But all eight eventual playoff teams came from the top 11 as of the end of November. The Blazers and Rockets were below .500 at this point but within two games of the No. 8 seed.

In 2014-15, the West had an obvious top 11 at the end of November and then a steep drop-off. All eight eventual playoff teams came from that top 11. (The Thunder started off that season awfully rough, missing Kevin Durant and Russell Westbrook. They eventually missed the playoffs by a game.)

Seven of the eventual 2014-15 East playoff teams were in the top nine on Dec. 1 of that season. Only the surprising Celtics (4-10 at this point) leaped into the postseason, and they were promptly swept by the Cavaliers.

In fact, going back the past 10 non-lockout seasons, the only teams to make the playoffs despite being below .500 and more than two games out of the No. 8 seed on Dec. 1 are those 2014-15 Celtics and the 2010-11 76ers (who were 2.5 games out in a high-parity East). With the exception of those two squads and very nearly the injury-ravaged 2014-15 Thunder, being below .500 and at least two games out of No. 8 at the end of November is a death knell for playoff hopes.

This season, assuming the standings hold two more days, this rule would apply to the Magic, Wizards, Heat, Nets, Sixers, Pelicans, Wolves, Suns, and Mavericks. Barring rare convulsion of league norms, the field from which 16 playoff teams will be taken has already been pared down to 21.

But there’s an important footnote to this observation, an adage good teams would do well to remember. While you can dash your playoff hopes in November, you can’t punch your ticket to the postseason this early. Last season, Chicago was 10-5 and in third place on Dec. 1. The Bulls missed the playoffs. The 2010-11 Jazz were 14-5 at this point and five games clear of the No. 9 seed. They missed the playoffs.

You can ruin a season with a bad November. But you can ruin a season with a bad December, January, February, or March, too. The opening month is important for sure, but so are the rest of them.