What efficiency gain did Coy's switchboard provide regarding physical infrastructure for 50 subscribers?

Answer

It reduced the physical infrastructure requirement to just 50 physical wires entering the building.

Coy's switchboard reduced the physical infrastructure requirement for the initial service pool of 50 subscribers to just 50 physical wires entering the building, whereas direct connection would have required nearly 2,500.

What efficiency gain did Coy's switchboard provide regarding physical infrastructure for 50 subscribers?
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