EXPERT: Knows How to Get Results
An expert is a person with proven knowledge or skill adequate to achieve a desired endpoint in a specific field.
An essential attribute of an expert is the accuracy of estimations of resources—time, money, people, etc.—needed to achieve a particular endpoint.
An expert might not be a professional—someone certified by an authority as one having knowledge or skill in a particular field. Although the two often overlap in one person, some professionals are not experts, and some experts are not professionals.
{EXPERT VS. PROFESSIONAL, ECPM, ENDPOINT TIERS, RESOURCE, FAIL FORWARD}