Most performance conversations happen in month nine, in a room with a producer, when somebody has to decide which characters get cut. Ours happened in week two, before a single final asset existed, and it took the form of a document that said: fourteen characters, under nine thousand triangles each, one shared material, no exceptions.
Treating it as a design document rather than a constraint changed what the art direction became. A shared material means every character has the same lighting response, which sounds limiting and instead produced the coherent storybook look people describe when they talk about the game. We did not arrive at that style and then find a budget for it. The budget produced the style.
The triangle number itself is less interesting than the fact it was fixed. When a modeller knows the number cannot move, they solve the silhouette problem in the topology rather than by adding geometry, and the results are consistently better than what the same person produces with headroom.
There were two exceptions we granted in twenty-two months, both for a single hero character in a cutscene, both reverted before ship because the difference was not visible at the camera distance we actually used.

