This is a great question! Even if you are satisfied with your current job role keeping your resume updated at least every six months is important. Here's why:
1. Keep track of all your accomplishments. Let's say you worked on a major project for your organization and the outcome of it's completion greatly contributed to the overall success, values, and mission of the company.
Including this accomplishment on your resume as soon as the project is complete will adds to your value as an employee and displays your level of commitment to the organization.
2. Be prepared for career progression opportunities. Let's say a position opens up within your company and they have decided to offer it to current organizational employees. The hiring manager asks you for your resume ASAP. To prevent the stress that will most definitely occur if your resume has not been updated in awhile, keep it relevant and current. You do not want to miss out on an opportunity because you were not prepared.
3. Remember the job is yours ... to lose!