Gets another cup, proceeds to place next to previous cup.

Repeat until no cups left.

ADHD is falling down a rabbit hole trying to find an answer to this question and realising that there IS actually a definitive answer, which turns out to be that it’s a “half empty glass” if the last thing that happened to it was that liquid was removed, but it’s a “half full glass” if the last thing that happened to it was that liquid was added, BUT you also have to factor in evaporation which is happening constantly, so really every glass that contains an amount of liquid that corresponds to half of it’s containment ability is actually “half empty” except for the few seconds after water was added to it, in which case it is, briefly, half full, then describing your findings in a single, insanely long sentence.

I used to do this with cans of soda when visiting my parent’s house. Their house was large enough I could easily lose one. I couldn’t remember if I had an open one so I’d just open another.

This really bothered my father.