Using my previous speculation
The general answer to the physics question why. For everything is that. What ever it is. It could make sense to a network.
Then my guess is that the physics phenomenon effects like the photoelectric effect makes sense if you view the atom as some kind of machine learning network.
So what can happen in a network? Well certainly problems can exist here also. One such problem is bad scaling. Too high values of some input.
Here I speculate that different atom networks have different sensitivity to value overflow on certain inputs. Then I guess it could handle this by diverting energy to more or different functions.
With this I predict there is a photokinetic effect. Perhaps the emdrive is such a device with a changed sensitivity due to construction choices.