The document outlines 5 common costly mistakes made in the hiring process: 1) Not properly defining what qualifications and skills are needed for the role. 2) Not consistently asking well-crafted, job-specific questions in interviews. 3) Relying too heavily on one person's opinion of a candidate, usually their own. 4) Conducting an incomplete evaluation of candidates that does not standardize information or use a team approach. 5) Hiring the best candidate seen rather than the one best suited for the specific position.