Apologies for digressing from the main theme, but there are a lot of misconceptions about NK.
It is not communist, although there are some parallel similarities. The official ideology is "juche," which you could translate as "self reliance."
After, the devastating destruction both Korea's suffered during the Korean war, the north rebuilt faster than the south, which had major problems of their own. Kim Il sung, the first President, acted like the CEO of a large company, spending all day on the phone coordinating industrial output and reconstruction. His son and successor Kim Jong il, refused to do that, and the co-ordination started to fall apart (as happens sometimes in capitalist companies) NK is however, undergoing change. Traditional industry is failing, the state claims there is full employment, but some jobs exist in name only, though the workers still have to turn up,and even though they do no work they still get paid.
Their official pay is likely worthless, although they may also get food, accommodation and other needs provided. But their wives may be part of the evolving market economy, operating small businesses selling whatever they can get their hands on, and attempting to accumulate funds in non-NK currencies.
It is also said that NK is completely cut off from the rest of the world. Not true, the outside world seeps into NK in a number of ways. First of all NK workers live in many other countries. North Korean restaurants have been opened in many outside cities, fully staffed by NK staff. Just occasionally, a worker deserts, but not so often. Labour hire work gangs also work in Siberia (that's known) and possibly in other locations.
The border with South Korea, is tightly sealed, but the border with China, particularly where there are large numbers of Chinese Koreans on the Chinese side, probably are very porous.
There are also large numbers of Japanese descendants of Koreans who were brought to Japan when Korea was part of the Japanese Empire, they are generally more sympathetic to NK rather than SK. There are lots of exchanges between these Japanese Koreans and NK.
Information comes back into NK on CD's - particularly of TV shows, and USB flash drives (which being small, are easier to hide).
All of these social factors means that NK changes, very slowly but in many little ways.
Rudiger Frank is a NK scholar, (and, in my opinion one of the better ones). He is Chair and Professor of East Asian Economy and Society at the University of Vienna and Head of its Department of East Asian Studies. He is also an adjunct professor at Korea University and the University of North Korean Studies (Kyungnam University) in Seoul. He holds an M.A. in Korean Studies, Economics and International Relations and a Ph.D. in Economics. In 1991/1992, he spent one semester as a language student at Kim Il-sung University in P’yŏngyang and has been researching North Korea ever since.
In this overview in the Asia-Pacific Journal he examines the way he sees NK changing: http://apjjf.org/2016/14/Frank.html
I see far more chance of NK changing than the JWs changing.