Recently I was reading an article about the need to track. Track performance and progress, that is.
The author mentioned that the act of tracking in itself is more important than what you choose to track. (For example, track the number of clicks or the number of unique visitors to your blog does not really matter, as long as you are tracking one of it.)
If you are running a business, blog or even monetising a hobby, remember to measure at least ONE key metric REGULARLY! That will ensure that you know, at all times, how well or stable your endeavor is.