system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it rumored that Macs do not get viruses as often as PCs do, and is this rumor true?
gpt
It simply doesn't make a lot of sense for someone to write malicious software to target Macs.  Windows has around a 90% market share.  

Since the goal is usually to spread to as many endpoints as possible, you want to target the broadest base.  That said, malicious software for Macs does exist.