The document discusses the Net Promoter Score (NPS) metric for measuring customer loyalty and likelihood to recommend a company. While NPS is widely used, the document notes it has limitations and may not be a reliable or predictive measure in all industries and situations. Specifically, NPS can be volatile, obscure other important information, and may not accurately reflect future business success or growth since loyalty is only one contributing factor. The document provides tips on how to use NPS more effectively by combining it with other qualitative and quantitative customer feedback metrics.