It's a throwback from yesteryear - when income used to be related to how often a piece was clapped. It was averaged out... so if you were the sort of person who clapped five times a month, you'd send $1 per clap. If you were the sort of lunatic who clapped 50 times every time someone completed a sentence, it would give everyone $0.000000001 per clap. Medium binned it off as a calculation tool a few years ago - but it's stuck around, like a weird ass appendix. I rarely clap anymore, some people clap everything - it's easy come easy go in the never ending world of Medium pivots :o)