Death, taxes, and assailing the job performance of a Red Sox manager, these are constants you can count on in a fast-changing world.

No one is going to confuse Red Sox manager John Farrell with Casey Stengel, but he did nothing during the course of a 93-win season that brought an American League East crown or a postseason that brought an expedited playoff exit to warrant losing his job.

Farrell is a serviceable manager. Despite protestations otherwise, that’s all you really need in baseball. This isn’t the NFL, where a coach like Bill Belichick can routinely impact the outcome of games. The manager is simply not as responsible for the outcome of games as fans and media with pitch forks and revisionist pitching changes would like to think.

Even if you think that Farrell often didn’t make the right moves from the Red Sox dugout, the Red Sox made the right move in bringing Farrell back as manager for 2017. The Red Sox’ future is bright with young talents such as Mookie Betts, Xander Bogaerts, Jackie Bradley Jr., and Andrew Benintendi. Like it or not, Farrell is part of that future, at least the immediate future. It remains to be seen if the Sox will pick up his option for 2018.

Firing Farrell after the Red Sox were swept by the Cleveland Indians and former Sox manager Terry Francona in the AL Division Series would have reflected worse on the organization than keeping him. If they didn’t do it after a 10-16 month of June or a shaky stretch in late July, there was no reason to do it following a playoff exit engineered by poor starting pitching and seven runs in three games from the best offense in baseball.

If you’re going to blame the manager for Rick Porcello serving up three home runs in four batters in Game 1 and David Ortiz batting .111 in the series, then you might as well blame him for the rain that washed out Game 3 last Sunday.

Farrell was handed a better team this season than he had in 2014 or 2015. Some of that was through addition. Some of it was through redemption and rededication on the part of players who dragged the team down last season. (Hello, Porcello and Hanley Ramirez.) The result was a 15-game improvement.

A manager’s impact on the outcome of a game is largely overstated, the result of 20/20 hindsight second-guessing and analysis that has more to do with the end result than the soundness of the skipper’s rationale. Outside of Grady Little-esque lapses in judgments, most grievances against a manager amount to rationalizing random events and unwelcome outcomes.

The first order for managers should be to heed the words of Hippocrates in “Of the Epidemics’’ — to do no harm.

Farrell didn’t do anything egregious in the playoffs. He probably managed better than he did in the 2013 World Series.

For those folks complaining about Farrell removing Benintendi for pinch hitter Chris Young in the seventh inning of Game 3, go back and look at Benintendi’s at-bat against Andrew Miller in Game 1. He was overmatched. He struck out on three pitches. Young was acquired because he hits lefties, and he worked a walk against Miller.

Most of the people complaining about Farrell pinch hitting for Brock Holt, a curious move, railed against his decision to elevate Holt to the second spot in the order in the first place.

Are there better tactical managers in baseball than Farrell? Absolutely. Francona is one of them.

But unless the Sox think Torey Lovullo, who has a significant role in the team’s preparation, can be one of those managers, there is no sense in moving on from Farrell, lest we end up with another Bobby Valentine.

There was a manager who had to go. He rode his bike to work, and like Spandex cycling shorts he rubbed everyone the wrong way.

The No. 1 job of a manager is to cultivate a culture where the players can perform to the best of their ability. That’s not just my opinion. It’s the one Red Sox president of baseball operations Dave Dombrowski expressed when he announced Tuesday that Farrell was returning.

Farrell did foster that environment this season, or at least he didn’t get in the way of it developing organically.

There are very few difference-maker managers in baseball. Joe Maddon, Francona, and Bruce Bochy come to mind.

Francona looked like a baseball Bobby Fischer the way he used Miller against the Red Sox to shorten games. But you can’t do that unless you have a dominant talent such as Miller and a deep bullpen behind him. Francona had both, and they performed.

The Sox’ hitters didn’t. Dustin Pedroia, Betts, Bogaerts, and Bradley went a combined 8 for 44 with zero runs batted in.

Bochy is as fine a manager as there is. He has won three World Series. But even he couldn’t compensate for a bad bullpen that plagued the Giants all season long — San Francisco led the majors with 30 blown saves.

An uneven bullpen ultimately ended the Giants’ streak of even-year World Series wins. It was their undoing, unraveling against the Cubs in the NLDS.

Bochy knows what he’s doing. But how smart did he look with inconsistency, uncertainty, and unreliability haunting his bullpen?

Conversely, Los Angeles Dodgers manager Dave Roberts looked like a Mensa member for bringing in All-Star closer Kenley Jansen in the seventh inning of Game 5 of the NLDS because Jansen and Clayton Kershaw, who got the final two outs on one day of rest, delivered.

We will always be grateful to Roberts for The Steal in the 2004 ALCS, but he can’t hold Bochy’s lineup card. Sorry.

Making Farrell the fall guy might feel good for a faction of the Fenway Faithful, but it would have been more dubious and illogical than any move Farrell made this season.

Christopher L. Gasper is a Globe columnist. He can be reached at cgasper@globe.com.