Your strength as a rationalist is your ability to be more confused by fiction than by reality.
Here are some instances where I learned something I found so surprising as to e.g. audibly shout "what?!":
When I want to set a recurring reminder for something, I use Google Calendar's email notifications. I wanted to set a reminder for monthly reviews at the end of the month, and so created a calendar event set to repeat "Monthly on day 31".
Soon after, I discovered something that incredibly surprised me. Can you guess what it was?
The calendar didn't generate events & reminders for any month with <31 days. This was not the desired outcome for an ostensibly monthly reminder!
I consider my memory to be terrible and make do with tools like such reminders. If I hadn't noticed this problem right then, I might not have noticed it for a long time.