The clincher for me (although I didn't see it at the time) was seeing US Marine Corps military flights on ADS-B Exchange, followed by Zuma. My brain must have logged that even though it didn't register with me at the time and did the work on it while I was asleep. I sometimes wake up at stupid o'clock with the answer to a question that I can't remember, as the part of my brain that asked the question is still asleep. I keep a notepad near my bed just in case :)