The mind is so integral to success.
A big mentality will allow for big results
If your mindset is that something would be difficult to do, it will be so, if that is not your mindset, then it would no longer be difficult. Likewise if you go about things in a very small way the potential for things to grow may be smaller than if you go for something in a very large way things will grow right away because of the momentum created by doing so.
A big mentality will allow for big results and a small mentality will only have small results. If one has a big idea but a small mentality it will be next to impossible to achieve it. If one has a small idea but a big mentality it will be incredibly easy to succeed. If one has both a big idea and big mentality there it is reasonable to succeed at it if persistent.
At the outmost limit perhaps an idea can be so big that it is limitless and thus to put this into effect, to implement would require a limitless mentality.