Regrets, he has a few.

Jeff Ulbrich revealed Monday some of the things that went wrong during his 12-game stint as the Jets’ interim head coach following the firing of Robert Saleh.

Ulbrich joined the Falcons as their new defensive coordinator after he held the same position with the Jets, who went 3-9 with Ulbrich as an interim coach.

The 47-year-old said a “lack of truth” was one of the biggest issues he experienced as the Jets spiraled.

“I learned even more than I knew the value of truth-tellers on your staff,” Ulbrich said.

“There’s certain things that need to be told to the head coach that are occurring because a lot of times what I found in that interim role was, although it was interim, it was like I felt the shift in the way people talked to me and treated me and what they said to me and the lack of truth sometimes was really detrimental, you know?

“So it just it reinforced the idea that [Falcons head coach Raheem Morris] is going to need me in that way, to make sure that I’m always telling the truth and maybe, you know, eliminating some of the blind spots that he doesn’t see.”

Ulbrich also realized that not delegating his defensive coordinator responsibilities after becoming the interim coach was a mistake.

“There is an element of a failure for myself in that way because I didn’t delegate,” Ulbrich said. “I didn’t. I just took it all on myself. In my mind’s eye, I was trying to create continuity and I didn’t want a fractious staff.

“I thought the best thing for me to do at that point in time was just try to keep everybody in the same role that they had just so we could keep things rolling. And it wasn’t the right thing to do. It wasn’t as I look back. I should have delegated. I should have given the defensive coordinator responsibilities to someone else.”

Ulbrich interviewed for the full-time Jets gig that eventually went to Aaron Glenn, and Ulbrich returned to Atlanta, where he coached linebackers from 2015-20.

— With AP