Think and Grow Rich
Napoleon Hill
The author of Think and Grow Rich, Napoleon Hill, is one of the godfathers around personal development and self help books.
A key chapter within this book focusses on 'desire'. Whenever you want to achieve something, whether that be a new PB, getting a new job or losing 5 kilos we all have some sort of desire towards that goal. Hill coins the phrase 'Burning Desire', where he says that if you do not have a 'Burning Desire' to achieve that goal, the likelihood of actually achieving it will be hugely diminished.
In other words, if you focus on the goals which you have a burning desire to achieve you will achieve them.