In various embodiments, an assembly for clamping and stapling patient tissue is disclosed. The assembly comprises a housing, a shaft extending from the housing, and an end effector extending from the shaft. The end effector comprises a staple cartridge comprising a plurality of staples stored therein and an anvil configured to deform the staples. The assembly further comprises a first rotary drive mechanism configured to change a distance between the staple cartridge and the anvil at a first rate during a first complete clamping cycle and a second rotary drive mechanism configured to change the distance between the staple cartridge and the anvil at a second rate during another complete clamping cycle, wherein the second rotary drive mechanism is further configured to affect the another complete clamping cycle independent of the first rotary drive mechanism.