alt Hacker NewsA-C cable assembly always works, CC signal is connected within the cable to Vbus via 56kOhm resistor, but that's only relevant to the downstream port, not to the upstream USB-A power sourcing port which does not have access to the CC signal. Upstream port provides power unconditionally within some limits depending on port type (CDP/DCP/USB3.0/2.0 data port/...).
That's how it's supposed to work, yeah.
But there is some trash out there in the world. A lot of it, actually.
Some naughty cables work with some naughty chargers work with some naughty devices. Postel's Law in action, I guess?
Usually the best place to fix it is by getting rid of the bad cables. Usually.