Say you are a programmer. You have some spare time. You have loads of talent. You want to write a great little addictive game that supports multiplayer. Maybe make a little money.
You are smart enough to want to build in automatic updates, user account verification, user skins, multiplayer server lists and so on. Your little home PC doesn't have the bandwidth, the up-time, nor the horse power to pull it off.
You can go to the cloud. They have bandwidth, storage space, up-time. Pay some money, get your VM on the cloud. You write your cloud "user admin" server. Write that fun little game. Sell over a million. Just don't use the name "notch", it's taken.
You cut the fiber at point A so you can install a tap down the line and nobody will know.
This isn't some terrorist plot. This is a Government plot to install data taps in California at the cross-roads of the internet. Check the building next to the manhole - I bet it has 10 floors but the elevator only shows nine floors...
>Does the cable need replacing?
Cables are made of wires, insulation, and connectors. Generally the wire and insulation have a very long lifetime. Even the insulation used in cheap Cat-whatever cables will probably outlast you.
The lifetime drops a lot if the cable gets flexed, rubbed, exposed to heat, UV, or moisture. Under those cases the wire and insulation can fail fairly quickly (think months to a few years).
Under normal use in a good environment the key failure point is where the wire meets the connector. Those mod-jack connectors rely on insulation displacement to make the contact. They can fail fast in bad environments (hot, wet, high vibration).
Still, it's not common for general maintenance to change the cables. It's more common to replace them as they give you trouble.
>Do CAT 5(e) cables get old?
Sure, but they tend to keep working.
Anything cut to length will be too short.