In his short time as NBC enertainment chief, Robert Greenblatt has gotten used to the pattern of its network’s executive sessions : They start with confessions, admitting failure and apology.

“I just want to get right to it,” he said. “We had a really bad fall, worse than I’d hoped for but actually.”

But, he added, it was “about what I expected. People keep saying the only place we have to go is up, which I do believe is true, but there’s a lot of work to do before we get there.”

Still, he ticks off the challenges: “We have few strong lead ins. Our most recent scripted hit is six years old. Some of our older hits lost important cast members this year.” Plus there’s the merger.

That might be a good thing, as Comcast is bringing money into the company.

Mostly, his mind cast back to the days when he led Showtime to its success and how easy things seemed then.

“If I was still at Showtime, you’d be calling me a genius for launching what? one or two good shows in a season.”

But NBC will unveil seven shows this season. “That’s about four times as many good shows as I ever delivered in any given year at Showtime,” he says.

“Unfortunately, the truth is that these shows aren’t enough to turn NBC around right away, and we don’t even know if all of them will be long term players or whether they will become true hits yet.”

“At Showtime, ‘Prime Suspect’ would have been picked up in the third episode and declared a hit and would have been probably in production for four or five years,” Greenblatt says. “But when you look at what it cost to make it versus what the ratings are versus what the advertising revenue is for that time period, you can’t be as cavalier.”

There is at least what looks like a sure thing – “Smash,” billed as an adult variation of “Glee” that looks into the building of a Broadway show.

“I think that ‘Smash’ is going to be very important to us,” Greenblatt says. It’s helped to by the fall lead-in of the summer hit “The Voice.”

When it came to “Prime Suspect,” he says, “we talked a lot about, “Is that too ‘cable’ a character for the broadcast audience? Is she too abrasive?” Maybe I should just blame the hat and move on.” The hat had been criticized by critics and the show never lasted more than five episodes.

“Ten or 15 years ago, you could keep a show on the air and slowly over time build an audience, “ Greenblatt says. “But we have a lot of evidence that a modern audience, if you don’t get them within the first four or five episodes, it’s really hard to get beyond that.

Of another canceled show this season he mused, “Was “Playboy Club” too dark? I think “Playboy Club” was just a rejected concept… I don’t think that people were that fascinated by that milieu and that place. And maybe it’s a little too obscure for them too. The Playboy clubs even though there are a couple of them that still are operating, that was a phenomenon from many years ago. So that didn’t connect.”

Asked if he was surprised that the comedy “Free Agents” didn’t work, he said sometimes the elements don’t always gel. “But am I surprised that it was that it went down? I’m really not surprised about anything going down these days.”

Of the future, he said NBC picked up five pilots for the fall before Thanksgiving with another slew coming next week.

Among the five is a remake of “The Munsters” as a drama, a Sarah Silverman project, one on a daughter with magic powers; “Beautiful People,” a drama about a robot rebellion; and a “Save Me” a self-help comedy that’s “cast contingent.”