This concept became popular due to Elton Mayo’s research in the late 1920s. Humans will improve their performance because they become aware of observation. This is now known as the Hawthorne Effect. You can read up on that with an easy search, being well documented.
My point is that we can learn a bit of our own psychological response by considering this effect. Anything we pay attention to is going to improve. This may not be because we have done anything of particular significance. By emphasizing something with our attention, we will improve our effort. As a consequnce the thing we focus on will improve.
Focused attention becomes the key. Other factors are important, sure. Yet, the key ingredient seems to be our focus. Stated in a simple fashion, we improve what we focus on. Focusing provides a magnification effect. You start to create waves that end up cycling back your way, often times, stronger than before.
Pay attention to the areas of your life that you want to approve. There is this wierd cognitive issue that we all do. We set goals to improve areas of our lives that we never spend anytime on. Success is not as complicated as we like to pretend it to be. If you want improvement quickly, just pay attention.