We develop leaders for life. You can be effective at work but if your life is not balanced as a whole, your overall performance (in any context), will be sub-optimized.
The use of positive practices is necessary to overcome the inertia of past habits. Will and determination are not enough to overcome the deeply ingrained habit patterns that occur both consciously and subconsciously.
Einstein's definition of insanity: "Doing things the same way and expecting different results!"