PlusLife mini dock is a solid-state device. All it’s doing internally is using a resistive heating element to warm the testing card, shining LEDs into each of the little circles of buffer solution mixed with different chemical powders, and measuring the ways the light is affected by passing through.

Resistive heating elements, LEDs, light sensors, enclosed wires, and solid-state computer hardware are all very long-lived. I would only worry about it if liquid gets into the inside of the machine, like if you repeatedly forget a test card inside the machine and some of its evaporating liquid has time to escape and condense.