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Knowing how to do something demonstrates technical ability.
Knowing what to do and when to do it demonstrates experience, judgment, finesse, and sometimes, political savvy.
Depending on what kind of role one is interviewing for, the interviewer may be interested in whether you can do the things they tell you to do. So little of hiring managers want people who can think; they want people who can do.
While I recognize that these hiring managers are short-sighted, I submit that they are the majority.
In spite of their preference, certainly an implementor has to make decisions about which choices to make all the time. Yet, many people view a 'programmer' as a do-er, not a decision maker.