This was supposed to be a British answer to America’s late night entertainment giants. A nightly mix of topical monologues, comedy sketches and chat modelled on the format that turned Johnny Carson, David Letterman and a host of men named Jimmy into stars and recently helped James Corden become a US household name.

Unfortunately for ITV its much-trailed new nightly talkshow, The Nightly Show, presented in its first week by David Walliams, with John Bishop, Davina McCall, Sue Perkins and Mel Giedroyc lined up for future slots, turned out to be more damp squib than firecracker with reviews variously calling it “awkward”, “unfunny” and “as flat as a Shrove Tuesday pancake”.

By the end of the week media outlets were dissecting the show’s sharp drop in ratings from 2.8 million viewers on Monday to 1.2 million on Tuesday. ITV argued that these were largely driven by the programme on air beforehand with big hits such as Broadchurch and Benidorm understandably driving more traffic than lacklustre fare like Play To The Whistle, however it’s worth noting that on Thursday the Prime Suspect prequel drew 5.3 million viewers of whom only 1.7 million stayed to watch The Nightly Show. Of far greater concern, however, was the related drop in viewers of the ITV News at Ten, which struggled to pull in more than a million in its new 10.30pm slot amid growing rumours that ITV has conceded the 10 o’clock news slot to the BBC and will instead aim find a commercial hit.

So why didn’t The Nightly Show wow? Is it even possible for a UK channel to create a successful chatshow following the US mould? And is there anything that ITV can do to turn things around? The answer to the first question is largely one of format and tone; the second and third: maybe but it depends on what they hope to achieve.

“These five-night-a-week shows don’t seem to work in the UK – maybe we don’t have the money to pay enough writers to come up with good enough gags,” says Bruce Dessau, editor of the comedy website Beyond The Joke.

“With The Nightly Show, specifically, there was just a general awkwardness about the first week. The interviews are too short and not very relaxed – on ITV a 30-minute slot is more like 23 minutes, which means the interviews are way too quick and superficial. That said, I do think you have to give them a little bit of leeway at the start. When Walliams interviewed Rob Brydon, for example, they’re friends and had more time together and the chemistry worked.”

Television critic Michael Hogan agrees, saying that the problem is one of execution. “The format is derivative but pretty solid,” he says. “The problem is one of tone. I think we do chatshows very well, from Parky to Harty, Wogan to Wossy, Norton to Alan Carr. It’s when we’ve tried to ape the Carson/Letterman/Jay Leno model that it’s gone less well.”

But why is that? It’s partially a question of slickness, but also of substance. “David Letterman welcoming Hollywood stars on to a big glossy set is a lot slicker than David Walliams interviewing Martin Clunes in a London theatre,” says Hogan. British chatshows such as The Graham Norton Show and The Jonathan Ross Show do nod to the US format, with Ross in particular clearly a fan of Carson and Letterman, but they also bring something of their own to the mix. Norton’s relaxed atmosphere and willingness to go with the flow allows his guests to spark off each other (who can forget Lady Gaga’s love-in with EastEnders’ June Brown?), while Ross, a genuine film fan, is a witty host, albeit one whose show has been lacking star power of late.

Facebook Twitter Pinterest Michelle Obama with James Corden on his Carpool Karaoke sketch. Photograph: The Late, Late Show/PA

By contrast, The Nightly Show doesn’t seem sure what it wants to be. Is it a broad light-entertainment show, as ITV’s director Kevin Lygo suggested during pre-show publicity? A witty nightly news show? A star-powered daily chatshow? The mix of topical comedy and sketches, which Lygo described as “covering some of the territory” of US behemoth Saturday Night Live, doesn’t quite hang together and there’s too often a sense that everything might shoot off the rails before grinding to a halt.

“Part of the problem is that in the US there’s a complicit way in which the host interacts with the audience to give an almost conspiratorial mood that doesn’t quite translate over here,” says cultural historian Joe Moran, author of Armchair Nation: An Intimate History of Britain in Front of the TV. “It’s also that hosting and putting together these types of shows is exhausting. It’s a very demanding format and American networks, being bigger, are better able to cope with those demands.”

Corden might have succeeded because he’s smart – but Carpool Karaoke wouldn’t have been as huge with British pop stars Michael Hogan

Nor does the decision to change the host every week, presumably in the hope it will generate audience and media buzz, help with coherence and flow. “The stunt hosting is a mistake,” says Dessau. “They should have had more confidence in one big name and given them the permanent job from day one. As it is, just as Walliams beds in he will be gone, same with the other guest hosts.” Hogan agrees. “The revolving host is a huge error,” he says, adding there’s a sense the UK is less attuned to the format. “A lot of Daily Show viewers in the US, for example, use it as a primary news source but we’re a bit more news-obsessed here. We’re a much smaller country and we have a different press culture.”

It’s also true that in contrast to Michelle Obama doing Carpool Karaoke with Corden, or Hugh Jackman yucking it up with Letterman’s replacement Stephen Colbert, The Nightly Show’s guest roster was both parochial and, rather more worryingly, too often linked to other ITV programmes. Thus Monday night saw Martin Clunes talking about the long-running drama Doc Martin while a later episode featured “all four judges from The Voice”. “It’s all a bit in-house pluggy,” says Hogan.

Despite this, ITV remains bullish about The Nightly Show’s chances. “We know that the figures will vary from night to night but it’s early days. In a creative business you have to experiment. We’re trying something new and different here and we’re just getting our head down and concentrating on making a good show.”

Yet while they should be applauded for taking that risk, Moran says audience viewing patterns tend to fall back on the familiar. Thus it’s easier to launch a late-night comedy chatshow in the US where the concept is an institution than in the UK where we prefer our daily talkshows at a different time, as evidenced by the previous success of The Paul O’Grady Show, which aired at teatime on ITV, and the current popularity of BBC One’s 7pm chatshow, The One Show. “The success [of these shows] proves that there is an audience for light-hearted daily chatshows. It’s just an audience at a different time of day,” says Moran. “One of the big themes of my book was the power of habit. It’s nearly impossible to predict why something will become a hit or what makes a winning formula but we can say that people get into habits of TV watching and in this country our rhythms are less attuned to a nightly show of that kind in that slot.”

Maureen Ryan, television critic for Variety, agrees. “In the US the format is certainly viewed as a way to recap the day and begin the process of winding down before going to sleep,” she says. “People do funny topical jokes, a few celebrities come out to promote their movies or music and it’s generally a light, ideally enjoyable way to end the day.”

She says the right host is key. “The humour on a late-night show can occasionally be biting and the interviews can occasionally be tense but generally what’s required is a host who is light on their feet and witty without necessarily being off-putting or overly cruel. It’s a hard skill to hone or acquire but there are a lot of comedians from the UK like James Corden and Craig Ferguson as well who are really good at being spontaneously funny and having a laugh without being too chilly or too nasty.” With that in mind is there anything ITV can do to up its game? Hogan says that even Corden, the darling of the US late-night circuit thanks to his assured hosting of The Late Late Show, might have struggled selling the format in the UK. “He might have succeeded because he’s smart, hard-working, talented and surrounds himself with good people – but Carpool Karaoke wouldn’t have been as huge with British pop stars.”

Despite that, Hogan believes the audience is out there for a US-style mix of chatshow and topical comedy. It’s just a matter of finding the right tone and host. “Charlie Brooker shows flashes of it on Wipe but I’m not sure he’s quite warm enough. The Last Leg [Channel 4’s late night topical news show] tends to be overlooked but it’s the closest we’ve got right now.”

Dessau agrees. “The right person could crack it though they’d have a harder job on ITV than on BBC where the show would be at least a full 30 minutes,” he says. “If it were a late night BBC show I’d suggest Charlie Brooker or maybe Phoebe Waller-Bridge but ITV at 10pm needs big ratings to justify moving the news, which is a very tough nut to crack.”

British chatshows

THREE THAT WORKED

PARKINSON (BBC1 1971-2004, ITV 2004-07) The grandfather of all British chat shows, Parky’s interviews were fascinating (Muhammad Ali), fatherly (a young David Beckham) and occasionally furious (Meg Ryan).

THE GRAHAM NORTON SHOW (BBC2 2007-09, BBC1 2009-present) Norton’s relaxed charm masks a strong interview technique. He lands A-list stars because of an ability to keep things light without being sycophantic.

THE LAST LEG (C4, 2012 to present) This smart, savvy mix of chat and satire is the nearest thing we have to a US-style late night show.

AND THREE THAT DIDN’T

DAVINA (BBC1, Feb – April 2006) Davina McCall’s show lasted for two disastrous months – here’s hoping she fares better hosting The Nightly Show later this year.

LILY ALLEN AND FRIENDS

2008 (BBC3 February – April 2008) The opinionated pop star’s talkshow made headlines when audience members walked out during the first episode. The show limped on for seven more.

THE MICHAEL MCINTYRE CHAT SHOW

(BBC1 March – December 2014) The BBC reportedly paid McIntyre £500,000, confident that the popular comedian would deliver a primetime hit. He didn’t.