David Stearns’ arrival to the Mets as president of baseball operations meant dumping the manager but keeping the general manager.

Why the two sets of standards?

“It’s my goal to build up the management talent in this organization,” Mets owner Steve Cohen said Monday, referring to the decision to retain GM Billy Eppler.

Cohen had hinted Eppler would remain in his post even before Stearns reached an agreement with the Mets last month.

Cohen added: “Baseball operations is pretty complicated. There’s a lot of moving parts. Building a strong management team is paramount to me. I viewed it as one and one equals three.”

A day earlier Buck Showalter was fired, giving Stearns a blank slate to choose his own manager.

Stearns said he’s comfortable working with Eppler, who previously worked as Angels GM after serving in an assistant’s role with the Yankees.

“Billy and I have had a really nice relationship going back years as competitors,” Stearns said. “Talking to each other whether it’s about transactions or about industry events. I have a lot of respect for the experience he has in this game, the experience he has in New York and I am looking forward to working with him.”

Stearns said it will take “weeks and months” working with the entire front office before he can delegate individual responsibilities.

Stearns said he will have conversations with members of the Mets coaching staff, but indicated he will wait until a new manager is hired before charting a course.

Third-base coach Joey Cora and first-base coach Wayne Kirby both have expiring contracts. Those under contract for next year include pitching coach

Jeremy Hefner, hitting coach Jeremy Barnes and catching instructor Glenn Sherlock.

“As a practice I like to have a manager involved in selecting the coaching staff and that is certainly my practice,” Stearns said.

As somebody who will be entrusted with adding prospects to the organization, Stearns was asked for his assessment of the Mets’ farm system.

“I am fairly familiar with it, and it’s better,” Stearns said. “This is a farm system both through maturation of some current players here and a clearly a very aggressive trade deadline I think got a whole lot better this year. There are, I think, some very promising players at the upper levels of the system and I am eager to get to know them better, to understand what our internal evaluations are of them, and watch them develop.”