Discipline is a word often used but the least understood. Discipline refers to a system where actions are controlled by certain almost fixed rules. So wherever there is systematic work, we find discipline. This way anything having a system of rules and regulations is looked upon as discipline. In this sense even subjects are considered disciplines. Every branch of knowledge is supported by a system of rules. There is no question of denying them. The grammar of a language is a good enough example of discipline. Without understanding grammar one cannot become a master of that particular language. Again mathematics or science has its own discipline. Because they are so well disciplined they have become exact Sciences. The law of the land is again another discipline.
Discipline or norms have spread to human affairs. In every walk of life there must be discipline. Thus if everyone is asked to keep to the left of the road and the people follow it then they are disciplined. In behavior also we speak of disciplined behavior. People at all levels have a way of behavior. If the outcome of such behavior is good for all then such people are said to be disciplined. This is often used to judge school boys. If they behave well in class, in public and at home, then we say the boys are disciplined. There can't be a better example of a disciplined organization than our body. How the various parts and organs of our body function is something wonderful; it is a marvel of discipline. So we can easily say the end product of discipline is efficiency; whether it be our body or a people there must be discipline.
Now the question speaks of discipline being at the basis of all achievements. What is achievement ? You try to do a thing and after many trials and errors you succeed. That is achievement; for instance an acrobat does something wonderful; it may be a physical act of a few seconds but for achieving it he must have worked hard for hours on end. A famous example is to run a mile within four minutes. The first man Banister to do it practiced it so vigorously and regularly that he did it. Now following his foot-steps many are able to run a mile, in fact within four minutes.
For such an achievement the mile runner ought to have a disciplined body. The astronauts have to go through a vigorous discipline before they can be put into space.
Take an example from the humdrum world. A man of business house becomes a successes. They cannot achieve anything by sitting and chanting a verse from the Bible. Thy work in a disciplined way. They know their goals, they know the loopholes and they know the pitfalls. Having known all this they work in a disciplined way and achieve success. This is true of an empire. When the machinery of government is highly disciplined, the government achieves best. The achievements of the English nation are worth remembering.
So this scene of discipline holds good even in learning. Take for instance learning to ride the bicycle. You have to follow certain rules strictly if you want to master cycling. Every young man who has learnt cycling knows this best. Discipline in learning may involve doing the right thing in a right way using the right tools. Learning very often involves humans and the learner must go to the right person. People who have studied chemistry do know this. In qualitative analysis there is what is called systematic analysis. If one follows it, very rarely will one miss; but if one adopts guess work, more often than not he will be wrong. So in learning also discipline is necessary.
To conclude, discipline makes life easier. It makes for achievements in all walks of life easier. Last but not least, it makes learning efficient, effective and lasting. But the best discipline is that which is developed within and not forced.