The room goes quiet around eleven, and that is when small sounds start to matter. A cable being plugged in has a click to it. The phone gives a short buzz to confirm it has started drawing power, and if the case is stiff plastic, that buzz travels through the wood of the table and comes back louder than it should be. Some people sleep through it. Some people notice it every single night and never quite say so out loud.
Wireless pads changed the shape of that ritual without removing the friction. There is no plug and no fumbling in the dark, but there is a coil, and coils run warm. A phone lying flat on a pad at two in the morning can sit at a temperature that would feel unpleasant in your hand during the day. Heat is not only a comfort question. Lithium cells age faster when they spend long stretches warm and full, so a slow overnight top-off at a lower wattage is often kinder to the battery than a fast one that finishes by one and then trickles for six hours.
Fans are the other thing nobody warns you about. Higher-output pads sometimes include a small active cooler, and it spins up exactly when the room is at its quietest. It is a thin sound, more of a whine than a hum, and it sits in the range that keeps light sleepers on the surface.
Alignment matters more at night than during the day, which is why the magnetic standard has been the practical fix. If the coils drift apart, efficiency drops and the wasted energy comes out as heat, and you wake to a warm phone that charged to seventy percent. Magnets remove the guesswork in the dark. The trade-off is that the pad has to hold the phone firmly enough that a thick case cannot introduce a gap.
Not every magnetic pad sits at the same tier, though. Qi2 pinned down both the 15W profile and the magnet array, while older implementations that predate it still ship with magnets of their own and look close to identical in a product photo. Korean retail carries a wide spread of these accessories because the domestic phone market turns over quickly and third-party makers compete hard on the small stuff, so comparison writing there tends to list measured surface temperature and coil counts rather than design notes, and this guide to Qi2 and magnetic pads works through where the certified tier and the older pads beside it actually diverge.
What ends up working for most bedside setups is unglamorous. A lower-wattage pad with no fan, positioned far enough from the pillow that any residual warmth does not reach you, and a case thin enough that the magnets seat properly. The phone will be full by morning either way. The difference is whether the table is silent while it happens, and whether the battery is still holding its rated capacity two years from now.