Even though its only a one point differene, it sounds way better to say "I got an 80" than "I got a 79", amirite?

Part of the human brain that reads the first number first. You know it's only one point difference, but your brain puts "79" into the 70's category, and "80" into the 80's category.

A B is better than a C... what's your point?

and if you completely fail, a low mark like 4% is more "impressive" than dead 0%