Overloaded means the same thing be it an Electrical Generator, a Trailer or a Communications service..
Generator,, Trying to power a 3,000 watt load with a 2,000 watt generator results in OVERLOAD, it can not "Haul the freight"
Trailer: Putting 5,000 pounds of stuff in a trailer that can only carry 1,000 results in flat tires and/or busted axles and frames.
Communications service... Trying to connect 5,000 clients to a tower that can only support 500.. Well either they get NO SERVICE or no bandwidth.
Right now I have bandwidth issues where I am.. But that's park Wi-Fi
Outside the park I have like 20 Gigs before T-mobile throttles me.