Magic had spoiled humanity. She’d rerun the simulation a dozen times, and each time they’d run up the evolutionary scales just as she’d theorized… and then suddenly plateau. She snarled in frustration at the constructs as they paraded about in their miniature world. There was too much at stake, her thesis, her reputation— she ruthlessly reset the program, reducing both the world and it’s inhabitants to dust.
There had to be a mistake in the programming, but she’d modeled them perfectly, she was sure of it. Every behavioral quirk, every base instinct, their fears, their dreams, and still nothing.
So she goes to get an actual human to help her figure out what’s wrong. He’s a theology grad student, so they don’t run in quite the same circles, but she’s seen him in the cafeteria and they are on friendly terms.
He looks over her notes and then asks to view the test she’s run. She lets him, still mostly positive her thesis is still correct and there’s just something wonky with the simulating computer.
He hops about inside the recordings and makes interested noises. Then finally comes back and tells her the simulations are correct. If she gives the humans the same magical abilities that her race has, it makes it too easy. Which she doesn’t get, but then she comes from a planet that spends most of it’s time trying to wipe out it’s inhabitants. He explains that Earth is a bit more placid and that the magic which barely kept her people alive gave the humans in her simulation something akin to heaven.
Any little thing that could be done with magic, was. Which mean all the little tools and tricks and ways of looking at the world that normal humans had developed never even occurred to them. Why create clothing when you could spell yourself warm? Why build a house to sleep in when you could simply spell the rain and wind away? Human developed the minimum amount of technology, and basked in the luxury they had. There was always some movement forward, for humans were a curious species, but there was never the looming threat of, well, anything to drive them forwards. Magic healed wounds, nurtured plants, carved stone, provided cool breezes on a hot day and warmth in the midst of winter.
And when it comes down to it, humans are content to be lazy.