What is design failure?

The difference between the actual features of the product $($or service$)$ and the features that the customer wants

Customer satisfaction with the total experience of a product or service.

The extent to which the actual performance of the product matches $($or is consistent with$)$ design specifications of the product.

Costs related to meeting customer demands and quality$-$related expectations.

An overall measure of quality is the difference between customer expectations and actual performance of the product or service.