What Exactly Does "Burn In" do for Electronics?

Scientists tested a frog. They cut off it's legs and they said "jump!"

The frog didn't jump.

Scientist therefore concluded that when frogs lose their legs, they become deaf.

It's not mine but I had to borrow it.

High end reviews are full of burn in for cables before they are reviewed. Google practically any cable review and you'll find it.
Claims can and will be made that are false and they will have their followers. Does it follow that all claims are so?
Can it be that 100% of cable burn in reviews being always for the better simply back up the claim that cables need burn in, thereby validating the claim?

All the best,
Nonoise

The change in the sound a new amplifier sends to the speakers as it gets more playing time is as real as it gets imo. Bass, for example, I've heard change substantially. The way bass loads a room can change and that change can be heard and felt several rooms away.

why is it that burn in always Improves the sound quality. If we were to believe that the sonics of a component do indeed change during burn in, does it make sense that the change would 100% of the time be for the better??? Of course not, ridiculous. 06-15-14: Jaxwired

Sound does not always improve with burn-in/break in. I've complained before that some power cords I've tried have lost bass weight and/or clarity as they had more playing time in my system. This was not a good thing in my book and a deal breaker. I can say too that the bass of some amplifiers I've tried tightened during break to the point that I did not care for it as much. Break in does not always bring about improvements in sound quality.

An ABX Blind Test
Here is but one example. Half got it right, half got it wrong, between highly rated Nordost Valhalla power cords and the cords that come in the box with the equipment.
I am not suggesting sonic differences do not exist between equipment and cables but, like Jaxwired, I believe it is easy in this hobby to perceive tiny sonic changes when the real reasons may be related to other psycho-acoustical influences.
Audio equipment testing
Wiki also provides some interesting discussion about objectivists and subjectivists.

"Is an audiophiles aural memory infallible? Of course not. Therefore the differences you think you are hearing could easily not be real"

If that's the case I guess you could turn it around and say the differences you think you don't hear could easily not be real...ha ha. Sorry.

Dragon I completely agree with you. My point is not whether or not the sonic differences are real my point is that we don't know for sure and that there is a possibility that we can be fooled or deceived by our ears. Since this is true, I like to consider more than just "did I hear a difference" when evaluating the worth of a product or concept like burn in. For one thing, I throw common sense into the mix. Certain products and concepts certainly are counter to common sense. For instance, cable risers, expensive feet under components with no moving parts, totem beaks, $1000 / ft cable, etc...