Too many people who you see in the gym, whether they be a weight lifter or a runner, do not keep track of how they are progressing. It is vital that you do this as someone who is trying to get better and move forward with what they are trying to do needs to be able to see how they are doing.
This is especially the case when you get further into your training regime and progress happens less quickly. In terms of lifting it is not your progress week on week that really shows how you are getting on. There are too many variables on a week on week basis, such as diet and sleep, but over a period of six months you need to be able to see how you are doing. These months on month progresses and changes are the real way of seeing what is really going on.
It gives you a sense of achievement when you are getting better, but you would never know unless you keep track of the progress. The sense of growth you get when you see and feel these changes are something that can keep you motivated. Too many gym goers become disheartened and give up their training after seeing the gains slow down after initial progress.
So when you go out and are trying to get better do not do the injustice to yourself of not keeping checks on yourself. We all need these checks, to keep us going or to keep us in check. The month on month progress is the most important, not the week on week.