"Moments of Truth" in services marketing was given by:

A "moment of truth" is typically defined as a situation in which the customer and the organisation come into contact with one another in such a way that the customer has the opportunity to form or change an opinion about the firm.

 Key Points

• In a bullfight, the bull's or the matador's (or potentially both) lives are on the line.
• When it comes to customer-company relationships, the message in a service environment is that everything is on the line at the crucial moment.
• Each service business faces similar challenges in defining and managing the moments of truth its customers will encounter.
• The former Chief Executive of Scandinavian Airlines System, Jan Carlzon, used the moment of truth metaphor as a reference point for transforming the airline system from an operations-driven business into a customer-driven business. 

Thus, the correct answer is Jan Carlzon.