There are two very important principles of psychological development that are relevant for traders.
The first is the use/disuse principle: Use it or lose it. We grow in the capacities that we challenge and exercise. What we don't challenge and exercise, we lose. There is no stasis over time, only development and decay.
The use/disuse principle forces us to examine our daily and weekly activities and ask ourselves which life functions we are using and which we are losing. Are we growing and developing physically? Emotionally? Intellectually? Spiritually? Socially? Professionally?
When we are in a use spiral, the energy we gain from growing in one or two of those areas catalyzes efforts to develop the others.
When we are in a disuse spiral, the energy lost from neglecting one or two of those areas gives us less fuel for growth in the others.
Much of performance is creating processes that ensure use spirals. Much of aging is living out disuse spirals.
The second principle is the mirroring principle: We are what we eat, and we are always consuming life experience. Everything we engage in life--the people we deal with, the activities we undertake--acts as a mirror, reflecting something about ourselves.
Over time, we internalize what is mirrored to us: if we have successful experiences, happy experiences, loving experiences, and affirming experiences, those emotions are what we internalize. If we are mired in unfulfilling work, hurtful relationships, and frustrating activities, the sense of self that we internalize becomes much more negative.
Much of life success comes from creating and maintaining the right mirrors.
And, of course, the very best life experiences are ones that push us to "use it" and, in so doing, create positive mirroring experiences--or what therapists call "corrective emotional experiences."
We don't change via motivation. We change by reshaping life experience.
Further Reading: Creating Change With Corrective Experiences