Someone had written on the internet and described self containment as being self reliant and self independent. As much as this is true, there is more to self containment than just a feeling of being self sufficient, of which you can never be since no matter how sovereign you think you are; you need other people to help you reach your destiny in life.
Most people do not realize the difference between contentment and self containment. Being contented is when you are comfortable and at ease with who you are and what you have, no matter the situation. Containment is holding back, it is self suppression or inhibition. I do not think I would want to live a life of no self expression. Sometimes it will do you good to let yourself go and live without so much self restraint. Life is a song and a song is supposed to make you have fun and enjoy.
Self containment makes a person want to be alone and do stuff on themselves, and avoid being with other people. It makes a person live a closed up life where they do not allow others into their world. The fact is, to make it to your destiny or to live a full life; you need other people as much as they need you. You need friends, colleagues, employers and most of all family. These are people who love you and believe in you.
Stagnation can feed on self containment. When you contain yourself from other people, it is hard for you to get challenged to improve on who you are as a person or at your work place because you will always tend to think that you are the best but you do not get to know how far others are. Containment can hinder your personal growth and affect your self esteem.