Why do people claim free Anti-Virus is better than Norton - NIS/360?

I have read on many forums about peoples sour taste on Norton Products , basically describing Norton as the devil itself .

Then they will proceed in saying that all the free suites are the best - i.e A.V.G / Avast .   

Apart from my one issue with Norton where it didn't find a virus , it has always looked after my system to the highest of quality .

 

At the moment i have - N.I.S 2012 & Norton Utilities 15 , and swear by Norton being the king of all Internet security.

 

How can a free suite be better , are they serious or just to skint to pay for a real Internet security ???