Wired routers require the wired cables to connect LAN devices. Running cat5 cable is substantial work that many prefer not to do and this is one reason wireless is popular.
Wired networks have these advantages:
1. Stability and reliability - as long as the cable length is less than 100 meters your connection is stable and reliable
2. Security - As long as you restrict building access, hackers cannot break in.
3. Speed - all wired LANS run at 100 Mbps; many are running at 1000 Mbps (1 Gbps).
4. PCS come with built in wired network https://www.procurepod.com
adapters and nothing more is needed on pcs