Why is work done in reversible processes maximum?

Hint:A reversible process in thermodynamics is one in which the direction of the process can be reversed to return the system to its initial state by producing tiny changes to some attribute of the system's surroundings. The system is in thermodynamic equilibrium with its surroundings throughout the entire reversible process. It has no effect on the system or the environment now that it has been reversed.

Complete step-by-step solution:
A reversible process alters the state of a system in such a way that the net change in the system's and its surroundings' total entropy is zero. In thermodynamics and engineering, reversible processes determine the limits of how efficient heat engines can be: a reversible process is one in which no heat is wasted as "waste," and the machine is thus as efficient as it can possibly be.
Because very little heat is lost to the environment, the work done in the reversible process is maximised. The endlessly slow reversible process will produce the most work. Because a lower amount of energy is wasted in the form of heat, the energy produced by the reversible process will do the most amount of work.

Note:The deviation from reversibility may be small if the system undergoing the changes responds considerably faster than the applied change. The system and its surroundings will be returned to their former conditions if one half cycle is followed by the other half cycle in a reversible cycle, a cyclical reversible process.