The process of converting thermal energy to kinetic energy is considered to be:

The process of converting thermal energy to kinetic energy is often characterized as poorly efficient due to the inherent limitations of energy conversion processes governed by the laws of thermodynamics. In any system where thermal energy is transformed into kinetic energy, a significant portion of the energy is usually lost to unwanted forms, such as heat dissipation into the environment, which does not contribute to the useful work being accomplished.

This inefficiency can be attributed to various factors, including friction, heat loss through conduction and convection, and the second law of thermodynamics, which asserts that all energy transformations will involve some degree of entropy increase. In many practical applications, such as engines or turbines, this means that only a fraction of the thermal energy input can be converted into useful kinetic energy. Thus, the overall efficiency of converting thermal energy into kinetic energy tends to be low, reinforcing the notion that this process is poorly efficient.