Each of you must have studied (it is possible that you do not remember) this in Chemistry in your childhood that

Every electron in an atom after attaining a certain amount of excess energy jumps to higher shell or orbit and remains there till it persists that energy.

This implies in our daily lives too, if you want to go to the higher shell or echelon then you have to work hard, attain energy required to rise up to that echelon and you will remain in that echelon till you persist that much energy. Being in an echelon is like being a spinning top, it will keep on spinning till it has energy.

Theory of Higher Shell explains us how there is no end point, you need to keep working to live in your shell and to go to higher shell you have to work more.