My TI 99-4/A would boot into a game or app in about 1/2 second after turning it on.
Of course it could take a while to load from a disk it you needed something that had been saved. Or even worse, trying to get something off of a cassette tape.
I wonder why they can't have the basics of the OS load from a rom or flash card. That way you can log in to the system and get started while waiting for non-essential stuff to load.
-JM
