Anyone under 40, who have no kids, don’t run a business, have no presence in the community, and socialize only with people under 40.
In theory, I could get a voicemail and then follow-up, but that would result in significant time wasted for both sides (e.g., calling doctors again or setting up re-delivery), and the total time I spent on dealing with spam calls is ~1 minute (5-10 seconds x 5-10 occurrences).