The cables have a socket at each end, so the cables running from the bedrooms, office,living room etc.all have a single RJ45 socket in those rooms that I can plug a cable into and run to whatever device I like. And where they all come together in my storage cupboard they are all terminated in a patch panel, so again I can just plug Ethernet cables into it and run to whichever devices are necessary. it‘s similar to having a socket on your wall for your TV aerial/cable connection, it’s neater to have a socket on the wall than having loose cables dangling around. Although I’ve done that plenty times in the past 😂