"I splice wires out of my hobby (repairing electronic products), so I can see how cables from SONY, ASUS, or APPLE differ from cables from an unknown company in China.". Please note that cheap doesn't always mean bad... and expensive ($10) doesn't always mean they're better than cheap ($3.00). But they are definitely not created equal.
So what is a good USB cable
They can charge quickly - which means they can conduct more current (amperes) from the charger to your device. It is usually because their wires are thicker, or they are made of better materials, such as copper rather than brass or aluminum.
Better external insulation - Some cables have poor external insulation that can peel off in time (I'm talking about Apple, Sony, and ASUS - what a shame). Some good but cheaper after-sales cables have nylon woven options.
EMI Shielding - More expensive cables (i.e., cables from Apple, Sony, Asus) have a metal shield wrapped around their main cable. This may be to comply with EMI standards, although it may not necessarily help the cable complete its work. This also reduces the flexibility of the wire, making it easier to tear when constantly bent.
Internal insulation - I have noticed that more expensive cables always have rubber insulation on each wire. The cheaper ones sometimes use strands coated with a thin coating.
Terminals - The metal terminals of some inexpensive cables can rust over time, which can be troublesome.
Flexibility - Some inexpensive cables feel too hard and uncomfortable. Personally, I prefer flexible ones because they tend to suffer less damage when repeatedly bent. Nylon braided cables are exempt because the braid itself is already harder.
