My powerbank requires its own cable for fast-charging?

[Abudis]

I've bought an APC powerbank the other day. The 10k mAh version, though the 5k version is pretty much the same. The powerbank has two output ports (one is 1.0A and the other is 2.4A), with a combined rating of 2.4A, both 5V ports. My device is a Galaxy S5+ and the charger that came with it is rated at 5.3V and 2.0A output. The cable that comes with the powerbank is rather small, so today I took my smartphone's USB cable in my bag and at some point I had to charge my device. 

And here's what happened. With the smartphone switched on, I could charge through the 1.0A port fine. But nothing happened when I connected to the 2.4A port. The powerbank didn't switch off (even though it automatically does when you disconnect it from your device) as if a device was connected. But no charge. Then i switched off my smartphone. Connecting to the 2.4A port, made the phone "reboot" again and again, showing that icon with the empty battery and the thunder, meaning you have connected to power, but didn't go on to show the "half-full" charging icon with the percentage and all. The 1.0A port again worked as expected. When I came home, I tried the USB cable that came with the powerbank. And both ports worked fine. 

Even though this isn't a problem at all, it got me thinking why it happens. Obviously the powerbank works fine, my smartphone's USB cable is working properly (I am charging it right now) and my smartphone does "accept" the 2.4A port since I did give it a 10-minute charge through the powerbank. The only thing that remotely comes to my mind, is that the USB cable provided with my smartphone has some sort of built-in "resistance" to higher that the stock charger's current, but I don't know if that is technically possible. Even if it had, it could just cap the powerbanks output at 2.0A, right? I don't know. I leave the explanation to someone more knowledgeable about electronics

[DiamondShark286]

your phone should draw however many amps it can take the cable shouldn't matter in the slightest unless the cable that came with the powerbank has some special jumper in it to activate that port.