What is the main disadvantage of using worm gears?

Worm gears are known for their unique advantages in transmission, such as high torque output and a compact design, but one of their primary drawbacks is low efficiency. This inefficiency primarily stems from the sliding contact between the worm and the gear, which leads to increased friction and heat generation during operation. The energy loss associated with this friction often results in lower mechanical efficiency compared to other gear types.

Additionally, the low efficiency is significant when considering applications that require energy conservation or high-power transmission. While other factors, like manufacturing cost or assembly complexity, may have their own considerations, the efficiency loss directly impacts performance and energy consumption, making it a critical disadvantage of worm gear systems.