What is a very important skil a person should lear1

What is a very important skil a person should learn?
What is a very important skill a person should learn in order to be
successful in this world to day? As far as I am concerned, I contend
that the skill should be the ability of introspection. There are many
reasons why introspection is the skill crucial to success, and I state
some primary reasons as follows. First of all, it is impossible for any
person that never encountered failure in his or her life. Since failure
is the essential and
unpleasant part of our life, what we should learn is the ability to
overcome it. Therefore, I deem the ability of introspection as the
skill that we should learn, because it is the most effective way to
overcome our failure. By introspecting ourselves, we could find the
reason that causes our failure and then we could learn from this
failure. As an old saying goes, failure is the mother of success.
Having the ability to introspect oneself means having the key to
success. Thus introspection is the skill to learn in order to success.
Secondly, we all know that success in one thing does not guarantee
the success in another. However, many people were still lost in this
kind of confusion and finally lead to their failure. To avoid this, we
should learn the ability of introspection. Because this ability could
make as awake in every step we do, every decision we make, and
this ability could guarantee our success in the long run. Thus it is
essential to learn the skill of introspection.
In conclusion, no matter it is success or failure that we encountered,
we all need to introspect ourselves, because this skill could help us
exam our behavior or decision, and this method is the secret of
success. Therefore, to learn the skill of introspection is important to
success.