  Molecular machines are stochastic systems that catalyze the energetic
processes keeping living cells alive and structured. Inspired by the examples
of F1-ATP synthase and the bacterial flagellum, we present a minimal model of
an externally driven stochastic rotary machine. We explore the trade-offs of
work, driving speed, and driving accuracy when changing driving strength,
speed, and the underlying system dynamics. We find an upper bound on accuracy
and work for a particular speed. Our results favor slow driving when tasked
with minimizing the work-accuracy ratio and maximizing the rate of successful
cycles. Finally, in the parameter regime mapping to the dynamics of F1-ATP
synthase, we find a significant decay of driving accuracy at physiological
rotation rates, raising questions about how ATP synthase achieves reasonable or
even remarkable efficiency in vivo.
