If you live in a room full of unhealthy food and five large televisions, it is only a matter of time before you begin consuming both.
In a battle between your willpower and the environment, the environment always wins in the long run.
So, if you are trying to change behavior, you are always better off altering the environment over testing your willpower. If you are trying to stop playing games on your phone, delete the gaming apps. If you are trying to eat healthy, surround yourself with healthy food. If you are trying to read more, make sure you have books easily accessible.
Don’t waste your willpower on battles with the environment. Use your limited willpower to create better environments and better habits instead.