"Brevity is the soul of wit."
Shakespeare said this and I believe it is one of the best things ever said about comedy. Colorful, poetic language is a wonderful tool in most writing and it has value in comedy too, but efficiency is king.
I think of it this way:
Every word I say in my setup has weight, and my punchline has to carry all that weight.
The stronger the punchline the more it can carry.
I can lighten the weight with some clever phrasing, or other smaller jokes in the set up on the way to the big punch line. This sometimes results in one joke becoming four or five related jokes, which is great. More often than not though I trim the fat and drop some words. Usually I find details that I included that serve no purpose other than that I found them interesting. If they don’t support the laugh, they go, and my set up becomes more efficient.
One of the biggest tells of an amateur joke teller is a bunch of useless details in the set up that do not support the joke.
With story telling stand up this applies to the individual jokes that make up the story (a longer story should be made up of smaller jokes). Each of these shorter jokes must have a punch line and the rules of efficiency apply. But if the story is 10 minutes long, even if all the jokes that make it up get good solid laughs, that last joke, the joke that serves as the punch line for the whole 10 minute story, better be one hell of a good joke, a joke that justifies the 10 minutes that led to it. I’ve rewritten stories, because a joke in the middle of the story was doing better than the one at the end. I found a way to put that stronger joke at the end, to carry that weight.
A writing exercise I use frequently is to take a joke I wrote and put it into Twitter (now the dumpster fire that is X) and then see if I can get down to or below the 280 character limit while still keeping the funny. This is also great exercise for isolating a joke and seeing I can make it stand on it’s own outside of the context of the story or longer set it resides in.
The brevity “rule” is also one of my favorite rules to break. A bit of poetic phrasing, a detail that gives the story depth and helps create my on-stage character and make that character believable can be a wonderful thing, but I know every time I do this I’m taking a risk of watering down my joke, of losing the crowd on the way to the punchline. So, I do it with caution and sparingly, and delight when I get away with it.