Repeating this mantra softly to myself has helped me sail through the hours of overwhelming tasks in a day. It has stopped me from rushing and I hate rushing. Rushing just sucks. It makes life feel hasty. I want to savor life. Even the boring parts.
This idiom also applies to anything you do. It has helped me improve my days.
When properly learning something new
Any new skill that you are trying to learn should first be practiced slowly.
Performing any action too fast will have you sacrificing technique which will in turn slow your development. It will also limit the greatness you could have achieved.