A skills gap analysis is used to analyze the difference between where someone is, skills-wise, and where they want to be. It evaluates someone’s current abilities and compares that to a future goal. That way, you can create a plan of action to bridge that gap by developing the necessary skills.
A skills gap analysis is often used in organizations as part of workforce planning. If they want to promote someone eventually, they can use a skills gap analysis to determine where to focus their development efforts. That way, they can train someone up to be suitable for the role they will eventually achieve.