Jo Brand has admitted to feeling intimidated by some TV panel shows where comedians vie for attention.
The comic, actress and Splash! judge said that many guests on the shows came off looking like they didn't say anything because of jokes bombing in scenes that weren't used.
She said: "There wasn't any element of competition or niggling or people treading on each other's lines which can happen in some shows when the testosterone gets going. That happens a bit in Mock The Week and I'm not saying that's a bad thing, but what I am saying is that it just doesn't suit some comedians to be on shows like that because they find it very stressful having to elbow their way in.
"Having done Have I Got News For You as a member of the panel, when you're on a show where there's people who have been on it for years and are very comfortable in their own skin and they know the other regulars very well and there's a sort of shorthand going on between them, if you arrive as a guest and you've just got an hour and a half to make an impact it can actually be very difficult.
"It's hard if you punt out a line and it just falls completely flat and the audience looks at you like you should be executed because you don't have any confidence to try it again. That's why sometimes you'll watch panel shows and you'll go, 'oh that person hasn't said anything at all' and that's because they've lost confidence early on by putting something out that didn't work and then feeling embarrassed about it."
Jo said she had suffered from the problem herself: "You try a line and nothing and you just feel sick, think 'Oh my God what do I do now? How can I crowbar in a joke from my set and make them laugh?' It is hard getting the confidence to do it."
Jo Brand's Great Wall Of Comedy invites guests to tell their favourite anecdotes about sitcoms past and present, and starts on Sunday June 16 at 7.30pm on Gold.