They don’t need to update well; they’re a compromise to achieve slightly more reactive lighting than ‘baked’ ambient lights. Perhaps one could describe it as ‘parbaked’. Only the ones directly affected by changes of scene conditions need to be updated, and some tentative precalculations for “likely” changes can be tackled in advance while pre-established probes contribute no additional process load because they aren’t being updated unless, as previously stated, something acts on them. IF direct light changes and “sticks” long enough to affect the probes, any perceived ‘lag’ in the light changes will be glossed over by the player’s brain as “oh, my characters’ eyes are adjusting, neat how they accommodated for that.”–even though it’s not actually intentional but rather a drawback of the technology’s limitations.