Change
Nothing stays as it is, everything is changing. Success is about learning in order to follow and create changes.
Changes in your surroundings will have to be matched by your changes. In this context, there are three levels of changes: can change, should change, must change.
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Optional Changes (can change)
In the first level, changes are optional. For example, you might have a bit overweight. It is barely visible and you do not feel too much of a difference. You might understand that your current way of life will increase the overweight. Currently, there is no urgency in changing to a more healthy alternative. In short, you can change if you want.
Recommended Changes (should change)
The second level comes with more urgency. Now changes are needed because things are out of balance. Coming back to the weight, your extra weight is now clearly visible and it also reduces your physical performance. It is still possible to delay action, but the current state hurts already enough to warrant a reaction. This means you should change.
Mandatory Changes (must change)
After you have ignored the signs of the first two levels, things become really urgent. You cannot continue in your old path; a change is inevitable either way. Your weight has now come to a point where your ankles and knee deteriorate and you have difficulty moving at all. This has made your girlfriend leave you. You also got fired from your job and now you have trouble paying the rent. In this situation, your life will change for the better or the worse. For yourself, this means you must change.
Kensho and Satori
Eastern philosophy distinguishes change and growth through insight (satori) and through small changes (kensho). Here, kensho is the situation that you want to change yourself and you work on it frequently (maybe every day). Then, when you look back after a year or so, you realize that you are a completely different person due to the accumulated small changes. Satori is happening when you work with some issue and you seemingly do not manage to make it work. You still persist and try different routes, and one day, things fall in place and you have a revelation of how everything is supposed to be. Please note that satori does not come out of thin air, but needs you to be prepared for the next step.
A very good explanation of the concepts is given by Michael Beckwith.