I feel that ZK was as much a solution to a 'problem' as it was the manifestation of an individual's personality and mindset; and one that doesn't generalize well. Not to mention full ZK is incredibly inefficient for most people.
Sometimes 'doing things to become more productive' is an easier problem to solve than simply being more productive.
Sometimes 'doing things to become more productive' is an easier problem to solve than simply being more productive.