>>33376585
There are 4 scenarios regarding knowledge:
- Known-knowns
- Known-unknowns
- Unknown-knowns
-Unknown-unknowns

You can't expect what you don't know you can expect or unexpect. That means you can't recognize what you're not awaiting to find, something still running in the background beyond your knowledge and awareness.

https://en.wikipedia.org/wiki/The_Invisible_Gorilla
https://www.youtube.com/watch?v=vJG698U2Mvo&t=45s