Ricky Gervais uses a 'salmon test' to judge his work.

The 'Office' star, director and writer learned his most important lesson about editing from an advert he saw for John West canned fish when he was a child.

He explained: "I remember seeing an advert when I was a kid and I've sort of lived by it.

"It was a pyramid of tins of salmon and a hand would come in and knock them all down except one and the voiceover went, 'It's the salmon John West rejects that makes John West salmon the best.'

"I remember the first time 'The Office' came in long and I thought, 'I've got to cut all this hot s**t out.' But now I love it - get rid of it all, whittle it down until it is the best it can be. They don't miss it, you don't miss it."

Ricky, 48, also revealed he is proud his TV shows, films and stand-up routines divide people's opinions and he is not universally popular.

He added to Shortlist magazine: "I relish the fact that probably more people hate me and 'The Office' and everything I do and everything I stand for than love me.

"And I wouldn't have it any other way, because that means you're doing something right. The last thing you want is to be a national treasure, because that means you really haven't done anything."