If you are talking DC supply sure.
If you are talking polarized capacitors, sure.
However you can't really install a non-polarized capacitor backwards, especially if the verry definition of "backwards" usually changes 50 or 60 times a second.
(Small, almost insignificant errors in the stated frequencys are part of normal operation of this system and can not be fully avoided, we ask for your understanding.)
Moisture will cause short circuits, duh.
Don't see how roaches can kill a soldered solid state piece of equipment though.
They might eat away at wires, but honestly, if a roach has enough time to eat through a wire, I would be more worried about why roaches a crawling through your electronics for so long without you either noticing or taking action.
Of course to high voltage kills components, that is the verry idea of a power surge.
How low voltage is supposed to harm equipment I don't really see though. Like, you mean that less power applied to it then it's supposed to handle breaks it?
Like, having a shelf that perfect well handles all the books sitting on it for years suddenly collapse after you picked up one of the books.
Sounds perfectly logical, sure...
"Dirty voltage" dosen't exist in DC supplies really.
I mean, it can, if the voltage suddenly and unexpectedly shoots up or reverses polarity.
Wait, fluctuating voltage that reverses polarity periodically, that sounds familiar, right?
(Yeah, of course hooking up a DC powered device to any AC supply will cause problems, but running an AC powered device on DC most likely will not work either...)
On AC it is indeed true that noise on a supply can reduce the lifetime of certain electrics.
That is why stereo systems, computers and actually a lot of normal appliances have line filters.
But as you know electronics so well you knew that already.
Heat of course can kill components.
Like, why do you think computers have elaborate systems designed to keep a component from overheating (aka CPU cooling).
Even some smartphones of today have heat pipes to spread the heat from the CPU over a bigger area to dissipate it more effectively.
And of course just holding the 2 sides of a supply together will cause a short circuit.
Like, your trying to tell me that the verry definition of a short circuit causes a short circuit situation and the resulting consequences/damage to arise as if I never visited 5th grade physics.
Actually, to make this even worse, no, just grabbing the life and neutral of a random socket and sticking them together will most likely result in basicly no damage to anything in the room.
The short circuit causes a huge current surge (I=U/R, U being your line voltage, R your wire resistance) turning all the wire basicly into a resistive heater for a verry short moment.
Then the circuit breaker cuts the connection to prevent a cable fire due to the current flow being absurdly much above the specification of the electrical system.
Grabbing a high voltage supply line and just smashing in into its counterpart causes havoc because of an entirely different effect.
You know that electricity always takes the path of lowest resistance.
If the supply line touches the other part of the supply line somewhere along its way, the path of lowest resistance is no longer down the line to the next traffo station as that traffo station is bigger load on the supply (aka a bigger resistance) then just two bare metal wires touching.
Thus, the power going to that transformer is suddenly cut.
Now, you still have the same supply voltage, but suddenly, the overall resistance of the entire system is cut significantly.
And we are not talking the AC of one house switching off, we are talking entire parts of a city suddenly no longer drawing power.
We know that I=U/R, and as U is consistent and R drops, I immediately jumps up.
It is like two people pushing against a piece of furniture that is about to fall over and suddenly one of the 2 just lets go and jumps back.
That person will be totally fine, but you suddenly have to endure twice the current flow UGH I ment weight of the furniture pushing and in turn, you get crushed.
Same if a power line touches ground.
Power suddenly no longer runs it's supposed path, overall load drops (a fault to ground is basically a 0 ohm path), current spikes.
If a lightning strikes a power line, the overall energy in the system suddenly spikes dramatically, thus current and voltage spike.
All of these things can mean insanely violent destruction of anything in the path of the current and not somehow protected by being separated by any component taking the brunt of the force (aka surge protector).
Our power grid is designed to adapt to changes in power demand pretty good and pretty fast.
It's actually kind of a fun amazing fact that there will always be the EXACT same amount of energy being put into the grid as is being needed at that verry moment.
It is always perfectly balanced.
How? Mostly huge moving masses in power plants. If demand increases, these flywheels physically slow down, pushing energy into the grid until the control systems can crank up the power out of what ever energy source that power plan uses.
That is why grid frequency always fluctuates ever so slightly.
Another fun fact there: The grid frequency is always 100% in sync with EVERY SINGLE generator connected to the entire grid.
That is why new power plants celebrate grid synchronization as the start of actual power production.
Oh, and, btw, I am studying engineering.
While not studying electrical engineering, I did pass my exam in the electrical engineering class I had to take last summer.
The exam was on the 19th of June last year, I prepared verry little for it and still passed with a 2.0 (1.0 would be the best, going down to 4.0 being the worst passing grade with at least 50% of the maximum achievable score being needed to obtain that), which is 0.8 grades above the average of the exam comparison group I was added to putting me in the top 36% of students in my exam group (13 of 36 exams in that group were a 2.0 or better).
That earned me 5 of my currently 50 ECTS credits towards my bachelor's degree.
Only 130 to go, yay.
So, before claiming profession in something, do a quick reality check of who you are claiming superiority against.
Really, being wrong is totally natural and as an adult one should be abled to stand up to that.
You won't believe how often I insist I am right only to realise that I totally misunderstand what ever the matter was and was the obviously wrong moron who made totally nonsensical arguments.
For real, daily would probably not even be a bad estimate when averaging those occurences over my lifetime.
