Matt Groening gave a brief interview with Rolling Stone about ending his long-running comic strip Life in Hell that's worth reading. He reveals that it was only running in 38 papers, compared to its zenith of 250 or so, which is pretty sad. I did make an effort to check it out every week in the LA Weekly, but when they dropped it there were no other LA-based papers to pick up the slack (at least, as far as I could find) so I haven't been able to read it on a regular basis for years. I did find out fairly late it was running in The Oregonian, though.
Some choice quotes:
Why pull the plug on Life in Hell now? Did you simply run out of jokes?
It's pretty obvious that I ran out of jokes a couple of decades ago - but that doesn't stop any cartoonist!
[A] TV producer sneered at the strip and said, "Why do you bother? Give it up." Because of that, I dug in my heels and kept it going two decades longer than I might have. I also liked the idea of having one slice of my creative output being completely solo, unlike TV animation. It's very satisfying to sit down at a drawing table by yourself and solve a puzzle with a deadline.