The power adapter is a device that converts the AC input to a DC output. The principle of its operation is mainly to close the IC control power switch to maintain a stable voltage output. However, this voltage must be rippled. In this case, the filter is used for filtering. The IC generally has no problem, so if there is a problem, the filter capacitor has a problem.
So we talk about the first problem in the power adapter is the capacitor, and the filter capacitor inside the adapter is the most vulnerable, but this is not absolute, you can give me the problem that other components will also be in use during the lifting process. Eventually the power supply will not work. But we are talking about the law of large numbers, not accidental.
The filter capacitor in the power adapter usually uses a point-solving capacitor. (The solid-state capacitor can also be used. The price is naturally very different.) The point-solving capacitor will have a high temperature during operation. Its service life is inversely proportional to temperature. The temperature is higher. High, the shorter the service life.