Fitwell

Builders would bring him their work beside the goal shape — the target they were trying to copy — and Fitwell would look. Not a quick glance. A real look. He would walk all the way round both shapes and check every single block: was there a cube in the build for every cube in the goal, and was each one sitting in exactly the right spot?

"It looks the same!" a builder said one day, plonking down a little house beside the goal house. "We're done, right?"

"It looks close," Fitwell agreed warmly. "Let's check, though. Looks-close and matches are two different words." He walked round. Front wall, right. Roof, right. Left wall — ah. One cube was missing, low in the corner, where the goal had a block and the build had a gap. "Not yet," he said, and he pointed straight at the little hole. "One block, right there."

The builder groaned, then squinted, then saw it. "That's it? One cube?"

"One cube is the whole difference between not yet and matches," said Fitwell. "But look how easy it is now — you don't have to redo the house, or wonder what's wrong, or feel like the whole thing failed. You just have to place one cube in one spot. I found it for you."

The builder set the missing cube in place. Fitwell walked round again, slow and sure. Every block in the goal had a partner in the build. No gaps. No extras. Nothing one square off.

"Matches," he said, and he meant it completely.