All attachments are rooted in selfishness.

"The space of the universe is benevolent to begin with and embodies the characteristic of Zhen-Shan-Ren. At birth, one is assimilated to the characteristic of the universe. Yet as the number of lives increases, a collective form of social relations develops in which some people may develop selfishness, and gradually their level will be lowered. If they cannot stay at this level, they must drop down further... in the end, they reach this level of human beings." (Zhuan Falun)

Looking at mankind, sentimentality and the desire for fame and gain are all due to selfishness. Without selfishness, there would be no fear, no jealousy, no fighting, no show-off mentality, no zealotry, and thus no anger and grievance.

For Dafa disciples in the Fa-rectification period, if we have no selfishness we will have no attachment to Consummation. Without selfishness we will always consider others first, we will not distinguish between those who are close and those who are distant from us when clarifying the truth to people, and we will not have the pursuit of comfort, as we will be thinking about the many people who are waiting for us to clarify the truth to them.

"I also want to tell you that your nature in the past was actually based on egoism and selfishness. From now on, whatever you do, you should consider others first, so as to attain the righteous enlightenment of selflessness and altruism. So from now on, whatever you do or whatever you say, you must consider others--or even future generations--along with Dafa's eternal stability." ("No-Omission in Buddha-Nature" in Essentials for Further Advancement)

After studying again this teaching Master expounded in February 1997, I further understood the harmfulness of egoism and selfishness and the great significance of attaining selflessness and altruism in this time of Fa-rectification cultivation.

This is my personal understanding. If there should be any mistakes, please kindly point them out.