Life is constantly shifting and changing.
It is unproductive to take a lot of time to plan for every known and unknown contingency.
On the other hand planning is necessary for the mind to focus and for the emotions to fill the end results with a sense of fulfillment, to reach a destination and to live a dream.
Kiazen is a mindset, a way of looking at the success in your planning process and the need for adaption to change. It means continuous and gradual improvement that includes goodness or virtue.