The air might seem capable of carrying an infinite amount of data,
but that’s obviously untrue. How do we know? Radio stations are broken
into channels to make sure they don’t overlap; various services, like
cell phones and television transmissions, also have specific spectrum
allocated to them.
The problem is interference, which is an issue that can impact a
Wi-Fi router just like it can impact a radio station. If another device
is using the same frequency and channel as your router, the performance
of both may be reduced. A common solution is to change the channel
setting in the router’s settings, but even this can sometimes fail.
Radio also has a limited range. The waves can’t penetrate dense
objects and can only project a certain distance before becoming useless.
A wall with heavy plumbing, or a large object like a furnace, could
degrade Wi-Fi performance if they intersect the router and the PC
wirelessly connected to it.
All of these limitations can be resolved by Ethernet. Official specs
put the range of Ethernet at 100 meters (almost 330 feet), which is far
more than is needed for a typical home network. There’s also no need to
worry about interference. Ethernet is very much alive and well in homes
that, for whatever reason, find Wi-Fi to be unreliable.
Source
