An electrical device that is plugged into an outlet but not used for its intended purpose can be dangerous. A charger from a mobile phone, not a charger, but simply plugged into the mains, can cause a fire.
Mobile phone owners often sin by not removing the charger from the outlet when the need to use it is no longer necessary. Some people wonder if this is dangerous or harmful. In principle, there is nothing wrong with the charger left in the outlet. There are several reasons for this.
Some believe that since the phone is not connected, then the charger does not consume anything from the network, does not consume electricity. This is not entirely true. Despite the fact that the current strength of a simple plugged-in charger from a mobile phone is zero, electricity is still consumed. Just in very small quantities. For comparison: a 40-watt light bulb "turns" these same 40 watts per hour. The charger only winds about 50 milliwatts per hour. Even the most economical and practical people can afford to leave the charger in the sockets around the clock, since the monetary savings (electricity bill) will be only a couple of cents a month.
The instructions for the mobile phone and the charger for it clearly state that for safety reasons, the charger that is not working for its intended purpose must be disconnected from the network. What can be the failure of this condition? In principle, nothing. Modern phone chargers are equipped with a built-in fire protection system. And there is nothing to burn in them, even if the device is constantly connected to the outlet. But this only applies to high-quality chargers. If the device heats up even when it is simply plugged into an outlet (without a telephone), it is advisable to turn it off anyway. It is possible that there is nothing to ignite there, but the plastic can melt. Especially if it's of poor quality.
What is the risk
The reason why you should overcome laziness or forgetfulness and still always remove the charger from the outlet are power surges. For example, if the electricity is suddenly turned off and then turned on again, the voltage in the outlet can increase from 220 V to all 380 V. Such a surge can render the device unusable or even cause a fire hazard.
During the summer, a charger left in a power outlet during a thunderstorm poses a great danger. It doesn't matter if the mobile phone is connected or not. Firstly, lightning during a strike can damage any electrical appliance, no matter what the strength of the current consumed by it. Second, the charger can catch fire after being struck by lightning, which is unsafe.