Danger, Will Robinson! Danger!
After watching well into Season 3, the robot FINALLY uttered these immortal words! I was beginning to think the most famous phrase in the series was some Mandela effect misquote, but at last he said it! Season 3, episode 11, "Deadliest of the Species."
Some mega fan has doubtless compiled a list of how many times the robot said "Danger!" and "Warning." He even said "Emergency!" once and once mentioned "danger" and "Will Robinson" in the same sentence but now that he said the actual phrase I can die happy.