You should be able to tell about the quality of anything just by reading how 
it's done.
Asking "why" it is of quality is a deconstruction process.
Basically it is an insult to billions of years of biological engineering.
Living beings have developed shortcuts in what we usually call proofs.
The least quantum of time gained by these shortcuts could well make the 
difference between surviving to and being killed by the immediate threat.
Lost in explanations, genius is killed by unprovability.