Give me six hours to chop down a tree and I will spend the first four sharpening the ax

Preparation is a prerequisite to success.

If you rush through this stage, you risk making mistakes or wasting your time and energy.

Take the tree for instance: by aiming to cut it down straight away, without first thinking to sharpen the ax, you have skipped the “preparation” stage. But if your tool is poorly suited to the task, you are highly unlikely to get the desired result. However, by taking the time to think about the appropriate method, you will in fact save precious time later on while ensuring that your action is effective.  

The required preparation is, therefore, both physical and psychological.

You can work hard, hustle, put in the hours, do the work, etc., etc., but the magic happens when you aim to perfect your skills beforehand.