It’s been a bummer of a summer for the broadcast networks.

ABC, CBS, NBC, Fox and CW rolled out a combined 12 new series from Memorial Day through July, and it’s a pretty safe bet that most, if not all, won’t be invited back.

This is in stark contrast to last decade, when shows including “Survivor,” “Big Brother” and “America’s Got Talent” thrived in the off-season, and went on to enjoy lengthy runs. But now, with so much new product thrown against the wall every summer, auds are clearly tiring, and not even giving shows a chance.

At the recent Television Critics Assn. Tour, ABC prexy Paul Lee called reality “a mature genre,” and that “it’s much more difficult now to find the shock of the new.”

No genre was more popular this summer than dating shows. But even as “The Bachelor/Bachelorette” franchise endures for ABC, Fox’s “The Choice” (average 18-49 rating of 1.7, and the strongest newcomer) and “Take Me Out” (1.3) joined CBS’ quickly yanked “3” (0.5) as dating-show duds.

ABC has struck out with, among others, improv show “Trust Us With Your Life” (0.9 rating), docu-crime show “Final Witness” (1.2) and voyeuristic competition series “The Glass House” (1.2 rating).

And then there’s “Duets,” the net’s biggest swing, and the beneficiary of massive May promotion; it averaged a mere 1.3 rating. The show may have featured big-name coaches like Kelly Clarkson and John Legend, but it did itself no favors by hitting the air one day after the conclusion of a TV season that saw a record number of singing contests.

And along with “3,” CBS couldn’t fetch much of a young-adult aud for its lighthearted “Dogs in the City” (1.1).

NBC’s only new show this summer was the drama “Saving Hope” (0.7), but it did OK with its first season of “American Ninja Warrior” (2.1), which had aired previously on cable.

CW bombed with ballet-themed “Breaking Pointe” and hotel-set “The Catalina” (both at 0.3) — but at least they were somewhat fresh concepts.

But the net apparently hasn’t gotten the memo about singing-show saturation, because it will roll out its own, “The Next,” this month. And there’s no reason to think it won’t be the next to disappoint.