EVERY customer, will always have CERTAIN EXPECTATION from the products / services that they deal with.
100% Customer Satisfaction from each and every product / service is not prudent to expect.
Every customer always expects a-lot-MORE than he gets for him money.
It is a COMMON PHENOMENON!? There are no hard and fast rules.
There is no STANDARD RULES that denotes that A-UNIT-OF-MONEY should get WHAT-UNIT-OF-PRODUCT / SERVICE.
It changes from company to company, time to time, season to season, product to product, region to region.
This is because of interaction of demand and supply, economy of people, reach, etc Therefore, CSI is very important, subject, to interaction of various factors, as mentioned above!