Why are these short USB cables not connecting my Android device?
It's possible that the USB cable is designed for charging only (i.e. not a data cable), or is of poor quality. 

Off-topic: Although not a USB cable, I have encountered OTG cables that could not detect a USB drive. In this case, it was a poor (or defective) OTG cable; other cables were able to detect the USB drive.

Related posts (external):


All micro usb cables are not created equal?