There is a couplet in our folklore which goes like this: "Janani jan to bhakt jan, ka data ka shur; nahitar raheje vanzani, mat gumavish nur". At first reading, it might seem like the author is asking the mother to produce a specific type of child. But if you think about it, what the author is trying to tell the mother, is to make sure that her children achieve their full potential. That means working towards achieving the right type of circumstances and providing the correct influences. The second line basically denounces mediocrity.
Your parents or teachers can try to teach you to strive for excellence, but ultimately it depends on the individual. One has to be exposed to excellence to really appreciate it. What generally happens is that kids strive to be better than their peer groups, either academically or in terms of income generated, or perhaps perceived social status. This is what is usually defined as ambition. But once they achieve that goal, people tend to sit on their laurels and enjoy the warm sunshine.
The pursuit of excellence is a lifelong process. One strives to do the best one can in every endeavor one undertakes. You try not just to do a good or acceptable job, but the best you can and try to better it the next time. Turning out work you can be proud of, is the foundation of the pursuit for excellence.
But the pursuit does not end in the workplace. This is a way of life. You keep on upgrading your education and your skill-sets and have a long term view of what you would like to do in terms of realizing your full potential. This will affect those around you as well, providing them with a better alternative or perhaps an example to follow.
Remember that your generation has a multitude of choices and is not bound by the constraints our generation faced while growing up, whether financial or social. As a young adult, you have the right to choose a mediocre existence for yourself and no one can fault you for doing that. But by doing that, you will be denying your progeny the opportunity to fully realize their potential.