I'm going over my third novel, The Tangled Lands, to release it as an ebook in a week or so. Written in the late '80s, it was set partly in a cyberpunk future that's now effectively an alternate version of our present. Which meant I was surprised when I came on a line about a smoking section in a bar. I never thought outright smoking bans would be so successful.
The line was not purely cosmetic, so I had to think for a minute or three before I found a new version for the book. Yeah, I could've left it alone. But it was the wrong place for something that's now distracting, and I like the new line better, so all's good.