You do not have one customer replicated hundreds or hundreds of thousands of times. Each and every one of your customers has a unique set of needs and values. Each and every one of your customers has approached your company from a different decision path. By measuring your customers to an average, so much rich information is lost.
To better serve your customers, you need to create relevant segments of customers. This can be through deep analysis of your internal data as well as combining it with data from other sources, e.g. shadow shopping, mystery shoppers, customer surveys, psychographics, focus groups excreta.
All analysis needs to have an objective. An objective of discovering how you can better and more profitably serve your best customers may lead to different segmentations than identifying under tapped customer segments. Do not approach segmentation with a canned approach. Be receptive to what your customer and your data are telling you. Good analysis is a dialog.