I attempted to game on my recently-purchased laptop (one of these), and I noticed something strange about the keys.

Within the first few minutes of playing, the keyboard feels fine. However, after a short amount of time has elapsed, the keys begin experiencing "sticking". Most prominently, sometimes a keypress is registered as having elapsed significantly longer than it was actually held down (tapping a key sometimes registers as holding down the key), or a keypress may be ignored even if it was the only key being pressed at that time.

This seems to happen most frequently with fighting games, where I am required to press the arrow keys extremely quickly in succession for long durations, in addition to the Z, X, C, and V keys used to carry out actions. No such problem occurs with StarCraft, even though I am constantly pressing a large number of keys, likely because no specific key is subject to continuous stress.

(The keyboard's rollover is not the issue here; all keys register even with all four arrow keys held down. I also checked the interior of the keyboard and it is nearly completely clean, so the keys are not physically sticking.)

Does anyone know what may be the problem here? I would appreciate an explanation for why this occurs, even if no solution can be provided.

Have you tried testing it with an external keyboard? Gotta figure out if it's hardware or software first (though I'm inclined to say software).

It's the hardware, no such problem occurs with my desktop keyboard.

Conclusion is obvious then, your laptop keyboard may simply be bad hardware. Or a connection has been loosed (unlikely).

My question asks why this happens. I know it is a problem with my laptop keyboard, but I need to know what, mechanically, is causing it.

Depends on the type of keyboard, laptop keyboards tend to be membrane type, meaning the problem is more electronic. Perhaps your debouncer is malfunctioning.