That headline is a bit exaggerated. Leaving a charger plugged in without a phone is usually not dangerous if you’re using a decent-quality charger—but there are still a few real reasons people recommend unplugging it.
Here are the 3 main ones:
1) Small but real energy waste (“vampire power”)
Even when not charging anything, a plugged-in charger can still draw a tiny amount of electricity. One charger won’t matter much, but lots of devices across a home adds up over time.
2) Heat and long-term wear
Cheap or low-quality chargers can stay slightly warm even when idle. That constant heat slowly degrades internal components, which can shorten the charger’s lifespan—or in worst cases, increase risk of malfunction.
3) Safety risks from faulty or cheap chargers
The real concern isn’t brand-name chargers, but low-quality or damaged ones. If a charger has poor wiring or lacks proper safety certification, leaving it plugged in increases (slightly) the chance of overheating or electrical issues over time.
Bottom line:
With a certified, good-quality charger, leaving it plugged in occasionally isn’t a big issue. The bigger risk comes from cheap knockoffs, damaged cables, or unstable power sockets—not normal standby use.
If you want, I can also tell you when you should always unplug chargers (there are a few specific situations where it really matters).