Therefore, a low retention rating does not mean that you will be laid off. It does mean that, in the event of a layoff within your major organization, skill code or job classification and level, in the normal order of layoff, those with R3 ratings will be laid off before those with R2 ratings, and those with R2 ratings will be laid off before those with R1 ratings. Your retention rating can drop for many reasons. In most cases these are related to the way performance is ranked and rated. It does not mean that someone whose performance is rated as R3, for example, is doing unsatisfactory work.
Unsatisfactory work is dealt with by management through performance discipline.
It does mean that management ranks the performance of others in the retention group higher. Change in retention group composition. Retention exercises occur about once each year. It sometimes happens that the people in a retention group can change from one exercise to another. Therefore, your work would be compared to that of different people than before, a change which may cause your retention rating to drop.