..... its just a open/closed switch, I bet it could handle hundreds of volts and 10+ amps and 1000000+ watts before it melts - its a switch as far as I know it has nothing in there to fail like a resistor so why?
Ehm ..... small switches usually holds just fractions of Ampere, some an Ampere or two, but it's not so easy .....
A switch is an electromechanical device subjected to a lot of different possible stresses and damages (and this is a thing that none take in consideration, usually) ..... it's not just matter of thickness of the pins ..... for know how a switch can work or fail (and become damaged) in a particular circuit, you need to know the thickness of the electrical conductors inside and outside the switch, the section of the contact area of the moving contacts, and their typology and movement type (plane, convex, gridded, multipoint, crosswaved, self-cleaning, rigid, elastic, sliding, pressing ..... just for say some) ..... then you need to know the circuit that is connected to the switch (it's a mainly resistive, capacitive or inductive load ? ..... all of them cause different stresses to the contacts, both in closing and opening action) ..... then you can start to have an idea about how your switch act, or fail, in the action .....
Damages can be melting, degradation of the metal surface coating of the contacts, "dirt" and oxidation of the contacts, springs that lost strenght and cause bad contact for too low pressure, "displacement" of the contacts (when a contact act bad and do conduction only on a reduced part of the contact surface, this point become more hot than normal ..... for high currents, this can become hot enough to "melt" or soften the plastic that hold the contacts in place), and so on ..... it's a very complex matter .....
Just for give an example, (cause if i try to write all about switches, tomorrow morning i'm still here finishing the post
) ..... a "clicky" switch like the one you can usually find in a laser host, can go from 500mA to 5A of possible current holding ..... but, if your circuit have a big filtering capacitor at the input of a driver that work with 1A, the instantaneous short-circuit from the capacitor, that happens each time you turn it on, can quickly ruin (in the worse cases, melt together) the contacts of a standard 5A switch, especially small ones with "forward" momentary function, so one can end asking himself "why the damn switch died in few weeks, on a circuit that use 1A, if there's written 5A on it ?" ..... without considerate that, closing it on a big capacitor, it can also take "spikes" of 10A
.....
Remember ..... never say "it's just a switch" .....
