High-quality TV lift cabinet motors are typically rated for 50,000 or more raise-and-lower cycles, which translates to well over a century of use at average household rates. Even in heavy-use environments like hotels or vacation rentals, a quality motor will last many years before needing any service. The mechanical components — lead screw, column, and frame — typically outlast the motor itself.
Longevity is a reasonable concern when you're buying a piece of furniture with a motorized mechanism built in. The honest answer is that, for quality products, the motor will almost certainly outlast multiple televisions — and possibly the furniture itself.
Lift mechanism manufacturers test their motors by running them through thousands of complete cycles — one raise and one lower equals one cycle — under rated load conditions. A mechanism rated for 50,000 cycles will complete that many under full load before statistical likelihood of failure increases meaningfully.
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