Richard Garfield, designer of Magic, once wrote on the topic of luck in games. He said that there is, in fact, luck in chess, because we cannot predict the outcome with certainty. ... there's still a possibility (however small) that he could happen to stumble upon a superior line of play, perhaps without even realizing it, and end up winning.

Incidentally, when I saw the title of this top-level post, I thought the argument was going to be something like what you've described here: when you make a move, you're steering the game in a direction that has an element of randomness because you can't really review all possibilities. And so you end up surprised at how good or bad it was for you.

Alas, it turns out that Gkalai was simply using a non-standard meaning for his words. Bait-and-switch.