You pour a cup of coffee at the coffeemaker, then you carry it to wherever you are going to drink it. You are liable to get some drops on your clothing or on the floor. I don't have that problem because my coffeemaker's carafe is also a vacuum bottle and I take the whole pot to my desk. Scientists, on the other hand, often must share a coffeemaker, so they have spent a lot of time studying the physics of coffee, coffee cups in particular, to figure out why they are so prone to spillage. It's physics.
Madelyn Leembruggen of SciShow explains the research done on this problem, which has to do with resonant frequency. If this video has your eyes glazing over at the science, get another cup of coffee and stay with it, because she also tells how to keep your coffee in its cup. There's a 32-second skippable ad at 3:45. -via Metafilter
"Walk without rhythm and you won't attract the worm."
And SciShow, 8+ million subscribers going for 13+ years at this point, is still making videos like a powerpoint rookie giving their very first public presentation...