After viewing this video six times, I'd like someone to explain to me how the program knew to autocomplete "z" into "zippers" without consulting the users. Coul

After viewing this video six times, I'd like someone to explain to me how the program knew to autocomplete "z" into "zippers" without consulting the users. Could it be that they've trained it for this specific sentence, making this entire video meaningless at best and a fraud at worst?