If one can consistently act contrary to their values, can that person honestly say that something is truly one of their core values? Can we act against deeply held, clearly defined values? I'm not sure that we can...it would be out of character.

Our values are the "why" behind what we do. They define what we stand for and the principles by which we operate.
When our values are not clearly defined, the conscience cannot perceive a violation and bring about a change in behavior. When they are not clearly defined, they are easily subordinated to urgent and/or unimportant matters.

Clearly defined values keep us on course. They are the GPS of the soul of an individual or an organization.