Network Equipment Waste rate

How much network equipment do you have to throw away every few years, new in the box? I have two brand new Cisco 3750X-12 network switches new in the box, never opened, that I have to throw away because the are end of Life/end of Support. Do you just don't have spares and rely on the Cisco overnight replacement warranty for failed equipment?  Every few years i always seem to have one or two network switches the company probably spent $5,000+ each that never got used. I like to keep at lease one spare on hand of my most common type of switches, I currently have four spare Cisco 3750X-12 , but only two deployed in my network environment, not sure who order so many extras, before my time.