What are these incentives? (I recently learned that examiners at the European Patent Office have no direct incentives for granting a patent and may internally

What are these incentives? (I recently learned that examiners at the European Patent Office have no direct incentives for granting a patent and may internally bill more working time if they reject a patent application instead. However, as rejecting an application requires a lot more research than granting a patent, examiners still might have an incentive to just grant a patent.)