Generally we do actions because we like, which means based on greed. In the main greed is our guide, desire is our guide, we like this, that and the other all the time, all the time wanting, wishing; and why?
Because of avijja (ignorance), not understanding the result of greed, without knowing the influence or power of greed.
Most people are unaware when greed arises; only when it is very intense, like lust, so that it cannot be hidden, only then do we actually recognize it, even though all the time it plays the predominant part in day-to-day existence. Most of our thoughts are about objects we are after.
Every time there is a pleasant sight, sound smell, taste or touch, greed is likely to arise. As long as we have greed without even noticing it, it will ask us to fulfil its wishes, to search, to direct us to the object we are after. So unless one sees that it is greed that is arousing, dictating to and directing us, unless we know the disadvantages of greed we shall never try to overcome this greatest enemy. Greed is like a magnet that drags to it anything that comes near, and it does this via the eye-door and beautiful sights; the ear-door and beautiful sounds, such as music; the nose-door and sweet scents, such as flowers; the tongue-door and delicious flavours; the body-door and touch of soft, smooth pleasant things; and the mind-door, thinking about all the enjoyable things we have seen, heard, smelt, tasted and touched, the characteristic of greed is grasping. Its function is sticking, like meat put in a hot pan. It is manifested as not giving up; and its proximate cause is seeing enjoyment in things that lead to bondage.
Men, when blinded by desire, are carried away by a powerful current, not realizing whither they are going, and where there are many who are blinded by desire for the same things, there is jealousy and rivalry. As they act to satisfy their desires, so they hurt and harm one another with resultant suffering.
To be attached to a thing is to be sad at the loss of it. To despise or hate a thing is to be unhappy at the approach of it. Selfish desire for a worldly object results in sacrificing spiritual treasure to secure the desired object which is probably of little value. Therefore selfish desire destroys the sense of value, for selfish desire places worldly possessions above wisdom, and personalities above principles.
Greed is grasping, wanting, trying to get. It can be changed by generosity, giving, sharing what we have with others. If we are going to stop going round the wheel of life, we shall have to become without tanha-craving, greed.