Cartoonists, like other humorists, are observers.
We pay attention to things — especially little things — that most people ignore.
For example, my family and I were recently on vacation and I saw an ad for a local pizzeria with the slogan “Best pizza … period!!!”
Do you see it? The whole point of their slogan is the “period” part, but they chose to end with not one, not two, but three exclamation points.
So one day when I saw on TV someone slowly slide over a piece of paper with a proposed salary on it to another character, I knew I had a good cartoon idea, period!!!