How can I troubleshoot a dishwasher spray arm that is not spinning properly?

To troubleshoot a dishwasher spray arm that is not spinning properly, first check for any obstructions blocking the arm's movement. Clean the spray arm and its holes to ensure proper water flow. Inspect the spray arm for damage or wear and replace if necessary. Also, make sure the water pressure is adequate and the dishwasher is level. If the issue persists, consider seeking professional help.