@rozzin The devices perform some kind of auto-negotiation to decide which way the power/data flows. But like everything automatic, it often fails. And devices rarely have a manual override.
The most popular incident was probably with the first Type-C Macbooks in 2015. If you plugged an Android phone into them with a Type-C cable, the phone would charge the Macbook, and not the other way around. Android has since added an override to the notification tray and I think Apple has fixed it too, but stuff like that keeps popping up all the time. And for things like powerbanks that have no software interface, and no hardware button for overriding, you're usually fairly fucked