We all like to live up to the expectations of our peers and as it turns out this doesn't appear to apply only to people but to nation-states as well. Almost prophetically, the North Korean government has conducted another nuclear test, detonating their first (allegedly) hydrogen bomb. Typically, a piece would go on from here to ask "Why Now?" and would then go on to talk about regional politics, instead I'm going to tackle this from the product engineering perspective.
While perhaps an unusual way to look at this process, a nuclear weapon is a product. In this case, the producer and consumer of this product are typically two separate government departments. For instance, in the United States the producer was initially the Manhattan Project which was run by the Army Corps of Engineers. The project employed 130,000 people and the cost to produce its product was then two billion dollars, which is twenty-six billion dollars today.
In other words, building a nuclear weapon is a massive undertaking. While it's likely that the overall costs of building a nuclear weapon have dropped since their first development, it's still difficult. The Pakistani Nuclear weapons program took 24 years to go from an initiated project to a real test. North Korea has on average conducted nuclear tests just over every 3 years.
In fact, the United States and Korea were expecting another nuclear test to occur (after the last one in 2013) as early as later in that year.
So what happened? My guess is what happens to many product engineering cycles, it was more difficult than they expected. The leap to producing a more advanced nuclear weapon is likely not as easy as it looks, and what major product overhauls are?
Looking at this further, it seems likely North Korea tested the weapon as soon as it believed it was ready to do so. It's been common in the past for North Korea to use actions like this to draw concessions from the US and South Korea while at the same boosting morale back home. It's sabre rattling that authoritarian states often resort to when situations begin to get more dire.
A Tenuous Hold
There is no telling with certainty what the future holds for North Korea and the region. However, it's reasonable to guess that the North will continue to act this way. They sit in a precarious position, and as their primary ally (China) develops they become yet more isolated as they become an increasing liability.
Any autocratic ruler wants to hold on to power, and this kind of behavior is usually helpful in attaining this goal, at least in the short term. However, it's clear that North Korea is still beholden to the difficulties of scientific endeavor and engineering. It will be interesting to see if the North Korean nuclear program accelerates from here, or if it will be subject to further setbacks and delays.