I would definitely shop monoprice over newegg for cables.

Not that Newegg sells them, but I've had bad luck with Monoprice's analog cables (1/4" or XLR).

Cables can certainly be DOA. Miswired jacks, broken strands... these things happen.

When wiring our datacenter, buying bulk ethernet cables, you'll find a bad cable every 100 or so cables. Still beats the failure rate of making cables yourself.

On the other hand, if I'm wiring them myself, I can just cut the end off and try again, since I've got a whole pile of ends right there, and the equipment to do it. If I'm relying on the bought cables, it could be quite painful to re-run the wire.

But that doesn't preclude the possibility of keeping a box of jacks and a crimp tool, just in case.