In the third chapter of his Hilkhot Teshuba Maimonides explains that in terms of religious behavior, we find three categories of people: rasha', tzadiq and benoni .
The rasha' (wicked) is the person whose balance of actions is negative. The tzadiq (righteous) is the one who has done more good than bad. And the benoni (average) is defined by Maimonides as the person whose good and bad actions are in a sort of a balance (3:1).
In the next Halakha (3:2) Maimonides clarifies that the calculation of right or wrong actions is inaccessible to us. This estimation does not depend on the quantity of Mitzvot we do or on any other factor knowable to us. Part of this equation relates to the unconscious psychological forces that drive us, our inner potential, the effect our actions have in other people, etc. Those are matters that only God knows exactly how to asses and only Him can take them into account for a fair judgment.
Now, since we ignore whether in His eyes we are righteous or, God forbid, wicked, how do we have to see ourselves?
When I see myself as a fully righteous person I might rely too much on my merits and do nothing further to improve my life. On the other hand, if I see myself as wicked, I might think that I'm beyond redemption and do nothing to improve.
Maimonides concludes that "a person should always perceive himself as and average, standing in a balanced scale between equal amount of merits and sins...". This balanced scale is not stable at all. Maimonides urges us to realize that since I'm in a balanced situation my immediate next action (or the next one, or perhaps the following one, etc.) will define if I'm a good person or a bad person.
The best self-motivation technique to live a life of constant improvement is to perceive myself constantly in the middle (benoni). Behaving and acting as if the very next action I'm about to perform will define who I am. My next choice is the tipping point of my entire personality.
"Life is like riding a bicycle. To keep your balance, you must keep moving."