Final answer:
Krug's Third Law of Usability states that users should easily understand the consistency and clarity of a website or application's interface.
Step-by-step explanation:
Krug's Third Law of Usability is a principle coined by Steve Krug in his book "Don't Make Me Think." It states that "A user should never have to wonder whether different words, situations, or actions mean the same thing." In other words, users should easily understand the consistency and clarity of a website or application's interface.