Joe Douglas has done his share of good things as the Jets general manager. He, too, has made his share of mistakes. 

With Morgan Moses, Douglas has done both. 

Douglas did a good thing by signing Moses in 2021 after the veteran tackle had spent the previous seven seasons with Washington, playing every single game from 2015-2020, spanning 96 consecutive starts. 

Moses was signed to a one-year contract and played 17 games for the Jets in 2021. And then Douglas made a mistake, opting not to re-sign Moses after the ’21 season and keep some continuity on an offensive line in flux. 

Moses signed with the Ravens that offseason and proceeded to start all 17 games for them in 2022 and start 14 games in 2023. 

Then the GM, acknowledging his mistake letting Moses leave the building, atoned for it when he traded for Moses in a deal with the Ravens last March. 

Since then, Moses has been what he was in the first place for the Jets when he was here in 2021 — a hardworking, consistent, inspirational leader on the offensive line. 

So, credit Douglas for righting his wrong. 

But it’s fair game to question why he ever let Moses walk out the door in the first place — especially as a former offensive lineman himself overseeing a Jets offensive line that has been a wreck under his watch more often than it’s been stable. 

Moses, the Jets right tackle, is one of the anchors not only of their improved offensive line, but of the entire team. 

It was Moses who stood up at halftime of the Jets win over the Texans last Thursday night at MetLife Stadium and inspired his teammates to play their finest 30 minutes of football in the second half to secure what was a must-win game. 

Moses, too, has quietly done amazing things that people on the outside of the Jets building don’t know about just to keep himself on the field. 

Moses revealed Monday that he’s been playing with a Grade 2 MCL tear with meniscus damage and a small bone fracture remaining from a left knee injury he sustained in the Sept. 19 game against the Patriots, which caused him to miss two games. 

In order to merely make himself available to play against the Steelers on Oct. 20, Moses had to have his knee drained before kickoff. 

These are things pros like Moses do all the time behind the scenes that few on the outside have any idea about. Moses makes no big deal about it. 

“Man, it’s pretty simple — you’ve got a band of brothers that you fight for every day and you never want to let nobody down,’’ Moses told The Post after the Jets win over Houston. “We built something beautiful throughout this offseason, putting this team together, and you don’t want to miss out on the opportunity. 

“These guys, especially on the offensive line, we’re a band of brothers. We’re like a shoestring going through a shoe. You want that shoestring to go through that sneaker as smooth as possible. That’s how we all five operate.’’ 

The knee drain before the Steelers game so he could play? 

“Man, it’s never comfortable, but you look to your left and you look to your right and you just want to be out there,’’ Moses said. “That’s just the love and regard and that we talk about every week for your brothers. You just want to be out there involved.’’ 

Jets center Joe Tippmann told The Post that Moses “is the best teammate’’ he’s ever had. 

“He’s a glue guy out there, he’s a guy that’s always pushing everybody,’’ Tippmann said. “There are times in the game where he screams out [from pain] and you’re like, ‘Hey, are you good?’ And he’s like, ‘I’m gonna keep [bleeping] going.’ It’s really awesome to see, just his relentlessness.’’ 

It’s not only the offensive linemen who notice — and are inspired by — Moses. 

“The crazy thing is he never complained about it, not one time,’’ linebacker Quincy Williams said Monday. “He’s just a hard worker. Guys like that don’t really complain or talk about all the stuff they got going on. They just step out there on the field and give us their all on Sundays or Mondays or whenever we need them. 

“When you know he’s sacrificing for the team, now I feel like I gotta go harder. He’s doing all this to get out there on the field, so now I owe him a little bit more, owe him another percentage.’’ 

Moses on Monday insisted that “everybody in this locker room is playing through something — whether it’s personal, whether it’s physical, emotional or whatever it is. 

“That’s what football teams are great for — because we band together,’’ he went on. “When I can’t give you 100 percent, I know the guy right there beside me is going to give the extra 15 percent or whatever it is. Being a veteran guy … you never know when it’s going to be your last time. I take that personally.’’