Why Are Expressed Customer Expectations Likely To Change Over Time?

Expressed Customer Expectations are those requirements that are written down in the contract and agreed upon by both parties, for example, product specifications and delivery requirements. Supplier's performance against these requirements is most of the times directly measurable.

Implied Customer Expectations are not written or spoken but are the ones the customer would 'expect' the supplier to meet nevertheless. For example, a customer would expect the service representative who calls on him to be knowledgeable and competent to solve a problem on the spot.

There are many reasons why customer expectations are likely to change over time. Process improvements, advent of new technology, changes in customer's priorities, improved quality of service