Rotating personnel disrupts existing conspiracies among collaborators. [causal]
Personnel are frequently rotated to extinguish established conspiracies of collaboration and cover-up and thereby maximize costs of conspiratorial reorganization. Intentional redundancies or duplications of function are structured into the division of labor to expose or compensate for the delicts of agents with overlapping responsibilities.
Shapiro, Susan P., The Social Control of Imper…, loc. 77