Why is it so important to take that step out of your comfort zone?

I have never taken part in debating competitions. I don't have the experience and have always thought I am not that good a speaker. So many public speaking and debating contests throw opportunity at me but I never seem to buzz. And then end up feeling bad that I did not use the opportunity. I never give my name for it with the thought that there are many other better people. But 1 fine day I just forced myself and registered for a debate event.
1) I was given a partner I never knew.
(Positive thought: Okay, I am going to meet someone knew.)
2) A topic on which I never had an idea was given
(Positive thought: I am going to learn something new)
                The day of the debate arrived. I went up to the stage. Spoke my heart out. Believed in the topic given and debated my heart out! I was told that my speech was really good. Ha! the tension was worth!

      What I just wrote about wasn't merely an experience. It was a lesson for me to step out of my comfort zone. To overcome my fear and face it boldlyFor most of you, going on stage and talking, debating might not be a big deal. But you will have definitely have other fears. To challenge those fears is what you call stepping out of your comfort zone.
HOW TO STEP OUT OF YOUR COMFORT ZONE?
a)Make  a list of your fears.
b)Look at it everyday and tell yourself that you have to get over them.
c)Make another 'to do' list and DO as many things you can when the right time comes.
d)It is okay to break out of your routine once in a while. For eg: Going for a cup of refreshing coffee on a refreshing day. This will not only boost your energy but also improves your mental framework.
These are few of the many things you can do to break out of your comfort zone.

Note: While it is important to come out of your comfort zone and explore it is equally important to make sure that you do not pressurize\force yourself to do something and land up in tension\depression.