When Shonda Rhimes of "Grey's Anatomy" and "Private Practice," Bill Lawrence of "Cougar Town" and "Scrubs" and Nigel Lythgoe of "American Idol" and "So You Think You Can Dance" were asked about the worst pitches they'd ever made on Saturday afternoon at the PGA's Produced By Conference, an odd thing happened:

All three producers said the worst pitches they'd ever made were the ones they made for their current hit shows.

At the panel titled "TV's Mega-Producers: Storytelling Across Multiple Series and Networks," which also included "Jersey Shore" and "Repo Games" producer SallyAnn Salsano, moderator Rob Kenneally of CAA asked the producers to think of the most gruesome experiences in their TV careers, no doubt expecting to get some anecdotes of long-lost projects and woeful experiments that never got off the ground.

Instead, Lawrence said his worst pitch was the one he made for "Cougar Town" (above), a series he didn't want to make.

Rhimes said hers was on behalf of the "Grey's Anatomy" offshoot "Private Practice," which came only after the network hounded her to create a spinoff series.

And Lythgoe said his came when he tried to sell Pepsi on the idea of bankrolling "American Idol," with a conversation that went something like this:

Lythgoe: "We’re going to audition lots of singers, and then take the best of them and the worst of them … "

Pepsi: "Wait. You're going to take the worst  singers?"

L: "Yeah, because that'll make great TV. And then we've got this English guy named Simon Cowell who is going to be rude to them."

P: "He's going to be rude?"

L: "Yeah. He'll encourage the worst singers to sue their singing teachers. It'll be really entertaining … "

P: "He's going to tell them to sue their singing teachers?"

Pepsi, he said, didn't buy it – but Coke did, and the rest is history.

For Lawrence, whose shows also include "Spin City," the question about his worst pitch brought an immediate reply.

"I've had four series on the air," he said, "and another four or so where we made a pilot but it didn't get picked up, and a bunch of scripts that didn't get pilot orders. But the worst project I ever pitched is 'Cougar Town,' and it's still on the air."

The show, he said, was initially mentioned to him by a network executive who said that former "Friends" star Courteney Cox was ready to return to TV in a new series with a ready-made title.

He went into the "Scrubs" writers' room and started joking about the possible series: "I told them that I could walk into ABC and say, 'Courtney Cox is 40, she gets divorced and fucks younger guys, it's called "Cougar Town,"' and I'd sell it in the room." That series became a running joke among "Scrubs" writers for the next three weeks, until he finally asked, "Should I really do this?"

He did, he did sell it in the room, and he was miserable for the first few episodes. Finally, he said, he overhauled the show and turned it into what he thinks is a decent show that happens to be saddled with "the worst title in the history of television."

Rhimes told a similar story about "Private Practice," which came only after ABC kept pushing for a "Grey's Anatomy" spinoff. She finally agreed to do a series on Addison Montgomery, the ex-wife of Patrick Dempsey's character from "Grey's" – and then, she said, she cast a bunch of actors she liked before she wrote a single script.

"I tried to write the script based on the actors, which is the worst possible way to work," said Rhimes. "The first nine episodes of 'Private Practice' were some of the worst television ever."

Lawrence quickly interrupted. "I'd put the first six of 'Cougar Town' up against them any time," he said, laughing. "It's be a crap-fest … "

" … death match!" concluded Rhimes.

Rhimes, though, said that the first season mercifully ended with the Writers Guild strike of 2007-2008, which allowed her to completely retool the show. Now, she said, she has far more freedom on "Private Practice," and on her new show "Scandal," than she does on "Grey's Anatomy."

"I can get away with anything on 'Private Practice,'" she said, "because the network is so busy looking at 'Grey's.'  It's like I have this shiny thing that gets all their attention, and this other thing where I can do whatever I want."

All three shows singled out by their creators have had personnel or network changes in recent years. Simon Cowell left "American Idol" in 2010, "Cougar Town" is moving from ABC to TNT in 2013 and "Private Practice" star Tim Daly will not be returning next season, while lead Kate Walsh is reportedly not confirmed beyond midseason.