This is classic advice, but I think it's fairly useless.

Consider this example, if you don't want to go to the toilet, no matter how much you imagine, you aren't going to push, climb etc., to reach it.

One needs a clear mission/vision though, in other words, to know what the "bigger reason" is for being in business. There has to be some reason like that, outside of just "getting filthy rich", otherwise your achievements will be limited by that attitude from the start.