Years ago I was working on developing a new cloud native service. The particular microservice I was working on had to call out to multiple other services, depending on the user parameters. Java 8 had just come out and I implemented what I thought was an elegant way to spin up threads to make those downstream requests and then combine the results using these fancy new Java 8 stream APIs.
I realized at some point that there was a case where the user would want none of those downstream features, in which case my implementation would spin up a thread that would immediately exit because there was nothing to do. I spent a couple days trying to maintain (what I saw as) the elegance of the implementation while also trying to optimize this case to make it not create threads for no reason.
After a couple days I realized that I was spending my time to try to make the system sometimes do nothing. When I phrased it that way to myself, I had no problem moving on to more pressing issues - the implementation stayed as is because it worked and was easy to read/understand/maintain.
To this day, I avoid the trap of "sometimes make the system do nothing". One day, that performance optimization will be necessary, but that day has not yet arrived in the ~7 years since then.