What is the point which make the client suddenly to change his loyalty from commodity to another one ? Price, Quality, package, Media, display.

At the begaining let us talking about loyality, when u have customet loyality that means u went beyond ur customers expectations, u not only satisfied them, this happed due to the great balance of all factores that u mentioned above, so, it is not easy at all to change loyality & when it happens, the most importatnt point is TRUST & a lack of Customer Respect, sometimes appearance of another commodity that is very close with1 or2 better aspects.

all the Factors mentioned can force a consumer to switch brand but often quality and media are the worst when a product percieved wrongly by the public, this factor forces immediate switching. price is often not a major factor because people who believe in quality will also spend money on good products think of Apple products, MERCEDES, BMW,Nike, starburks coffes etc. these products are cost differentiated, the day their quality is  beyond expectation is the day their market dies. Quality strategy is one of the greatest factors in consumer perception.