Denis Norden — English Writer born on February 06, 1922,

Denis Mostyn Norden, CBE is a retired English comedy writer and television presenter. After an early career working in cinemas, he began scriptwriting during World War II. From 1948 to 1959, he co-wrote the successful BBC Radio comedy programme Take It From Here with Frank Muir. Muir and Norden remained associated for more than 50 years: after they stopped collaborating on scripts, they appeared regularly together on radio panel programmes My Word! and My Music... (wikipedia)

It's like your children talking about holidays, you find they have a quite different memory of it from you. Perhaps everything is not how it is, but how it's remembered.
And when you're on your own there is that terrifying possibility that you may be the only person on the planet who thinks it's funny - and you have no way of finding out.
And if you can offer an explanation as to why it doesn't work then you've got to the whole root of comedy.
Then after that came word processors and it's hard to make those laugh.
The comedians all finished their acts with a song. They would get a certain amount of money from the song publishers and would use that money to pay the writers. None of them paid very much for their comedy material, but it all added up.