The rotation proponents believe rotation prevents officers from suffering burnout, staleness, and getting set in their ways. They believe these issues can be particularly problematic for full-time SWAT officers who might develop an elitist attitude because of extended isolation from the rest of the department, resulting in a detrimental "them against us" attitude on both sides. Rotation, they say, combats this by ensuring a constant influx of "new blood" to prevent a distinct separation.
A second benefit is rotation distributes SWAT-trained personnel throughout the department, making it more versatile and professional. Also, SWAT officers will be encouraged to seek promotion, resulting in SWAT influence at the command and administrative level.
As Long As You're Willing and Able
The opposite view is officers should remain in SWAT as long as they are qualified, pass all requirements, have the right attitude, and want to be in SWAT. The main argument for this position is SWAT is a specialty that requires a significant amount of training and experience to reach the desired level of performance and to create a cohesive team.
Arbitrarily rotating out personnel, according to this school of thought, results in the premature loss of valuable experience and leadership, and it disrupts the team, which has to constantly rebuild. There are many "veteran" SWAT personnel throughout the nation, who have been in SWAT for many years, whose experience is both valuable and vital. Allowing these veterans to remain in SWAT results in a more experienced, better trained, cohesive team that functions smoothly and efficiently, and ensures successful missions.