The motives behind Lucifer's fall were, first, his desire to dominate Adam and Eve, which was derived from his pride and jealousy, and, secondly, his impulse of love toward Eve.
Lucifer coveted Adam's position and the greater amount of love which Adam and Eve received from God. Lucifer's desire to receive God's love as much as Adam did was not, in itself, evil.
But when he left his proper position and seduced Eve to fulfill his desire, he violated the Principle and created disorder in the whole cosmos. Adam and Eve were equal and were to stand before God as a unit when they reached maturity.
Lucifer was to be under Adam and Eve.
Contrary to the divine order, Lucifer dominated Eve, and she, in turn, dominated Adam through temptation. In this way, the order of dominion was reversed.
That aspect of human pride which leads people to regard themselves or their creations as God or God-like derives from the fallen nature of the archangel Lucifer.
If Lucifer had loved Adam as God did, he could have shared God's joy and happiness with Adam.
Because Lucifer became jealous of Adam and tempted Eve, he left his proper position and took a stand against God. When we stand with God, we feel joy and power.
If we stand against Him, we destroy not only ourselves but also others. This disruption of proper order has borne bitter fruit. Eve multiplied her sin by seducing Adam. Ever since, people have multiplied sin through ignorance.
Young Oon Kim