it is very important to understand this. it may seems like you are improving yourself all the time and that consequently your results should go up steadily too. however, it doesn’t work this way in practice.
in reality you will train for quite a long time without feeling any real progress; but then (once you’ve got a critical mass of small improvements) you will make a sudden leap forward.

it is very important to understand this and to not lose your enthusiasm prematurely.