The study of molecular motors or supramolecular materials that require a non-equilibrium steady state to achieve their function provides a way to try and understand the operation of similar systems in biology, where they are ubiquitous. Conversely, their ubiquity in biological systems is often used to justify the potential importance of synthetic non-equilibrium systems. It is undoubtedly true that chemical driven networks allow some behaviors, such as continuous operation of molecular motors, that are not possible by switching between equilibrium steady states. However, as these related fields mature, it is important to start to consider where they might have the greatest impactit is not obvious that we will use synthetic systems for the same reasons and in the same way as they are used in biology. For example, biological molecular motors are required to operate continuously without user intervention. The same is not true of artificial systems where energy ratchets may be simpler to apply. Put more bluntly, although both birds and rockets fly, the inspiration for the Apollo program did not come from biologyour imagination should supersede biology and not be bound by it. This is not to say that the design and operation of new systems that can achieve a non-equilibrium steady state should be judged based on their applications. In the context of molecular motors, very few working systems have been reported and many questions remain to be answered 8 (e.g., how to optimize systems to work against load and maximize efficiency 57 ) and challenges overcome (how to couple controlled molecular motion to the wider system to do work or achieve other objectives).