If the role of claps needs to be explained, then it's a lousy metric. Medium doesn't have a "Rate this article from 1-50" button. From that, I infer that claps do not serve that function, so I am not going to appropriate the device to provide that function, especially when other readers are not doing so.

If it were up to me, the maximum number of claps would be one. The idea of using less than fifty claps to express any level of disappointment is ridiculous to me. (It does have a sort of zen feel to it, though - the sound of hands not clapping and such.)

I clap once if I agree and up to five times when I'm thinking "Thanks for saving me the trouble of writing an article." I believe claps are seen by many as a metric of unique happy readers, and I believe high-number clapping distorts that message. As an author, I would much rather know how many people liked my piece than how strongly one or two fans liked it.