We stock as many different lengths, in one foot steps between lengths as much as possible up to 12' for HDMI and Ethernet. Speaker cables, analog audio, and IR (which is essentially going to be gone for us in racks now that Comcast has working IP control) are made custom. It's a pain in the ass to try to find space for and neatly manage extra length of patch cables. We pride ourselves on the appearance of our rack work, it's a big part of our brand. The only thing that makes them more serviceable is the ability to look at the back of a component and clearly see what things are connected to without having to manually push other cables out of the way.