There comes a time in any doormat's life where it just can't stand it anymore and this is usually indicated by a tear or the gradual fading of the "O" in "Hello", leaving the word "Hell", which is very much an indication to where you're going to step in.
If this doormat is in human form rather than fabrics and text, well then its life isn't any better. The real question is, do u think that "Once a doormat, always a doormat"? I don't know, but I like to observe people and I have noticed that if you ARE a doormat in one aspect of your life, you're probably going to be controlling some other situation in your life. Why?because as humans we always strive to have the power over stuff, whether emotionally or through possession or even through the commodities we were blessed with.
The point is that nothing is constant and there will be a day in this doormat's life when it starts to make your life the living hell that people are invited to enter. So, try to be nice to people next time you feel all high and mighty, it might not be very rewarding, but it sure saves the emotional build ups that creates psychos.