Some of the most common forms of inappropriate conduct are arguing with someone who isn't interested in learning, pushing yourself to physical exhaustion, drinking too much, or over eating. All of these actions result in loss of qi, they create a deficiency. Historically, starving may have been the most common cause of qi deficiency.
Qi deficiency simply leads to conflicting emotions. Of course this is a natural process, so for instance, if you get in a bad argument and then you go home and take a bath and go straight to bed, you will completely recover. The problems arise when your conflicting emotions combine with someone else's, and it's already past midnight and you have a meeting early in the morning, so you don't have time to replenish your qi.
After a few days of this people start thinking about how they can get more power. Deep conflicting emotions probably arise from fear of death. I think the quest for power is part of our hard wiring. It is triggered when our survival feels threatened, and it arises so that we will be able to survive extreme hardship.