"The way I talk about it is, every time we present a product on air, America votes," said Scott Crossin, director of broadcast operations. "We have instant visibility to how our customers respond in real time."
Lisa Robertson, an overnight program host, said the pressure of immediate sales results could contribute to stage fright for some vendors. "In about four minutes you are going to know if you're working or not, and your sell is going to be done anywhere between six and 12 minutes," she said. "That's a lot of pressure."
Such pressure, with the added ingredient of live television, has made for some infamous moments through the years. Archival clips from the QVC channel of vendors falling off ladders or fainting have become underground hits on YouTube.
"I had one poor gentleman who came on the set, I introduced him, he said, 'Hello' -- that was the last word he said," Robertson said. "He completely froze."
John Kenedy took the stage to sell a product called Tanda Clear, which promises to banish acne using a special blue light. It was his first-ever outing as a QVC vendor.
"It went well," Kenedy said afterward. "I was very nervous. I thought I was going to lose my voice, but you get through it. The host is fabulous."
As a QVC host, Robertson is something of a cross between a TV anchor, a salesperson and an entertainer. A lot of her job, she said, is knowing the products she's helping to sell.
"You can't say you own it if you don't, you can't say you're going to buy it if you aren't, you can't say you've used it if you haven't, you can't say you love it if you don't," Robertson said. "You have to be clear."
Not everyone may be familiar with Lisa Robertson, but does she ever have fans. Many QVC viewers are fiercely loyal and seem borderline obsessed with the network, the cult of QVC.
"I love QVC; I'm a QVC queen," said Charmaine Greene, who was shopping at the QVC outlet adjacent to the studio. "We do a lot of ordering."
Wired magazine once described shop-at-home viewers as "trailer-park housewives frantically phoning for another ceramic clown." But don't tell that to Pam Henriquez and Linda Weaver, who drove an hour and a half to shop at the outlet mall.
"It's always a treat for us to come down and spend the day down here, because we go to the outlet and then we go to our favorite restaurant right up the road, and then we go to the studio and buy more," said Henriquez, adding that she buys something from the network every week.
It's not just about the shopping, though, she said. "It's entertainment. I learn a lot."
Greene said, "I try to watch daily just to get my QVC fix, this is what I call it. I turn the TV on at least a few times a day just to see what they are selling. And if, then if it's something that I am interested in, I just watch."
Back in the studio, the women from NuFace -- Catalano and her colleague, Carol Cole -- were nervous. It was 2 a.m., and this was their product's big debut, make-or-break time. Before the NuFace vendors went on air, Robertson offered pointers.
"When we start out with this, I need us to start out with something very impactful," Robertson said. "So instead of just starting describing what it is, I need for you to kind of, up front, to talk about it being a microcurrent device that is based on the same technology you would find in professional offices."