Psychopathy aside, some people have no regard for others because it does not affect them if they don't. Such is life - sorry.
The abstract noun of "selfish" is "selfishness." It refers to the quality or state of being focused on oneself and one's own needs or desires over others.
Oscar Wilde made a very good quote about selfishness, "Selfishness is not living as one wishes to live, it is asking others to live as one wishes to live." There are other good quotes about selfishness from other people such as Albert Camus.
Because you are thinking about yourself instead of others.
"Human selfishness has brought many species to the brink of extinction".
Greed and selfishness often lead to conflicts and harm because they prioritize individual desires over the well-being of others. When people act out of greed and selfishness, they may exploit others, hoard resources, or prioritize personal gain at the expense of others. This can create inequality, injustice, and conflict, contributing to many of the problems faced by humanity.
If you believe in moral law, and you are responsible for how your actions affect others, then you should worry about the consequences of your actions. Generally, a selfish person does not care about how they affect those around them. They do not care about the consequences of their actions. Selfless, or considerate, persons, take the time to consider what the consequences of their actions are on those who are around them, and act to ensure their actions do not negatively affect others. Jesus was the sublime example of selflessness. He sacrificed Himself for the sake of others. Lucifer is the prime example of selfishness. Lucifer craved glory and even built a throne above God's in heaven. Selfishness is the root of all evil. Selflessness is the root of all love.
He thinks he is better than others That is not the definition of selfishness. Caesar was very vain, thought he was better than others, but he was definitely NOT selfish.
Her selfishness is the thing which will be the reason for her failure. This is the sample sentence using selfishness.
Greediness is a metaphor for selfishness for no amount of thing you have will you ever think of another.
Nowadays it's Selfishness, Selfishness and Selfishness!
A common theme related to selfishness is the idea that selfish actions ultimately lead to negative consequences for both the individual and those around them. It often explores how selfishness can damage relationships, hinder personal growth, and create inner turmoil for the person who is solely focused on their own needs at the expense of others.