Selfishness

I understand that everyone including myself bound to be a little selfish from time to time. What i couldn't understand is how can someone be so selfish that they never ever consider the situation of the others and only thinking about themselves. They can do anything or telling absurd lie just to get what they want from you. And you don't have to emphasize on that "word" because that only makes u more like a liar in my eyes. Thank you for showing me how harsh reality can be.