Amount of caffeine consumed by a team may be an interesting proxy for how motivated employees are at a company (a small amount indicates high motivation, a medium amount indicates low motivation, and a high amount indicates either a severe lack of motivation or a high level of motivation).
It has two scary effects: one is it seems to sacrifice some creativity for some raw output (along with a sort of scattered and less human feel to communication).
Two is that it degrades sleep quality. Which probably means a lack of memory formation at the margin over long time periods.
These are just hunches but people on caffeine just have an attitude that’s a little off putting once you notice it. I’d love to see some big studies that focus on the long term and subtler psych effects.
Without coffee, I will feel sluggish and sleepy all morning. With coffee, I feel alert and inquisitive. I have a rule against drinking coffee after noon, so it doesn't affect my sleep patterns.
Discovering coffee in college was really what allowed me to read things for long hours. I like the fact that it activates inquisitiveness a lot more than that it enables productivity. This is a purely subjective experience, I admit.