Malnutrition and disillusionment take their toll on the North Korean military.
Rimjin-gang reports that the NKPA is finding that after a full generation of hunger and depressed birth rates, there are fewer young North Korean men who meet its physical standards, and many of those who do dodge the draft. I’d assume that draft-dodging in North Korea requires one to have the financial means to pay significant bribes, and if the possession of such financial means is still largely a function of songbun (hereditary political caste), then the disillusionment has entered the middle and upper-middle castes, too.
For those seeking more background on hunger in the North Korean military, see the links at the end of Rimjin-gang’s article.