Answered by Rachel, Hiring Expert at Eaton, on Friday, June 6, 2014
You do not necessarily have to include all of your previous jobs on your resume, especially those that really fall outside of what your core history and focus of employment was and is now. That being said, any sort of gaps on your resume will make any good HR professional pause when looking at your potential fit for a position. It could be as easy as a brief conversation with a recruiter explaining that you took on work to make you financially solvent during a challenged economy while you were trying to find a role in your field. This explanation is valid only if your resume truly reflects this by showing stable employment in your other positions. On the other hand your resume could be overlooked due to an unexplained gap on your resume. This situation is more likely if the rest of your resume does not demonstrate stable employment prior and subsequent to the gap.
You are correct in saying that a diverse set of experiences can be a strength for some individuals. It can show that a person can be flexible and adaptable, as well as being able to demonstrate proven success in varied circumstances. A resume like this demonstrates the potential of a strong hire, if the variety of experiences include promotions and increasing levels of professional advancement and leadership. On the other hand this same type of resume is problematic if there is a significant amount of variation in roles and that those same roles do not demonstrate advancement, but rather, the resume looks like the person does not have a clear concept of who s/he is professionally. To a potential employer that type of resume indicates someone who is potentially flighty and unreliable. If you are not sure what your resume is truly saying about you it may be helpful and worth your time and effort to have a professional review it and provide you with a constructive critique.