The account says that the Korean-built tankers matched the contract specifications. British requirements then changed during construction, while the builder was unwilling to stop work and redesign the ships around those changes. This left the delivered vessels different from what British officials wanted by that later point. Meeting an agreed specification can still produce dissatisfaction when the customer's requirements change during the build.
Notable Point · 2:16:36-2:17:28
The tanker example: a completed contract and changed requirements
British dissatisfaction with tankers bought from South Korea is attributed here to changing requirements after the original specifications had been agreed.