Haha.. Yes it's obvious in hindsight. I think a few factors played into it. First was an underestimation of the half life of caffeine. It stays in your system

Haha.. Yes it's obvious in hindsight. I think a few factors played into it. First was an underestimation of the half life of caffeine. It stays in your system for a while, and stacks when you have multiple throughout the day. Another was my personal sensitivity to caffeine with regards to sleep. I know many people who can't drink coffee at all and others who can drink it as a digestif. I'm somewhere in the middle. The last is being embedded in a coffee-drinking culture, without personal awareness of the above two points. So I would drink it later than I should with people who didn't (or didn't know they) have a problem drinking it at that time.