Final answer:
The efficiency of a simple machine is always less than 100 percent due to energy losses.
Step-by-step explanation:
The statement in the question is true. The efficiency of a simple machine is always less than 100 percent because some small fraction of the input work is always converted to heat energy due to friction. This loss of energy as heat is inherent in any machine and is described by the concept of efficiency. Efficiency is defined as the ratio of useful work output to the total work input, and it is always less than 1 or 100 percent due to energy losses.