In an interview originally featured in Japanese strategy guides and now available on Shmuplations, the legendary developer and producer of Super Mario 64 discussed the game’s development at length. When discussing playtesting, Miyamoto revealed that the team had a group of 10 middle schoolers, including his own child, play around on King Bob-omb’s stage, Bob-omb Battlefield.
“Seeing him try dozens of times, over and over, to get up this unclimbable hill, as a parent I couldn’t help but think, ‘Geez, does this kid have any brains?’” Miyamoto laughed. Thankfully, the children’s abilities (or lack thereof) aside, the playtest had been a success. “Afterwards we asked the children what they thought of the game, and they said it was fun, and that they wanted to play it again.”
It’s a good thing they saw firsthand the beginnings of understanding that when players are given an open 3D expanse to explore, even with a set goal in mind, the fun is as much about the exploration on the journey to get to that goal as it is about completing the goal itself.
I also wonder, from watching those kids play and try to break the boundaries of the game, what he would think of all the grown adult speedrunners and YouTubers who do all that as a hobby now, lol.