"USB C" refers only to the connector size, shape and available contacts. What changes, cable to cable, is how the connector is wired and what type of wire is used. On the simple level you can see a bit of whats up here when you notice that the cable doesn't work, or work well, but then flip the USB C connector around 180 and then it works. That's actually wrong, not supposed to be that way, but some (cheaper?) cables are sort of half-wired. Some will also fail as a charging cord if the application requiers too much current for the wire size used, there's a resulting voltage drop, inadequate current is delivered, and the device being charged doesn't even recognize the attempt. This happens with Lightning cables too, and also shouldn't based on the intention of the connector standards.
If you find a good USB C or Lightning cable, make a note of what it is and buy a bunch. They also fail with use.