Actually the weakest link is the one responsible for the operation/maintenance of the equipment. The human!

Purchase and install quality and it lasts.
Take care of it and it lasts.
Buy cheap and don't whine when it fails unexpectedly.
Switches have parts that wear. So it's safe to assume they will need periodic replacement. But so do gimbals. And servo pots use to require regular cleaning and lubrication. And how many antennas have been broken and replaced?

I've never had a switch fail. But I have had servo connectors fail. And servos themselves fail. And even a battery or two. But never a switch.