Overloaded party lines

Telephone delays
Inadequate telephone system
The very rapid increase in the number of telephones installed has resulted in overloading of exchanges often using out-of-date equipment. Technical incompatibility between such exchanges, particularly in different countries, can lead to considerable delays in making a connection. The situation becomes worse in peak periods and is aggravated by time zone differences which limit the overlap in office hours between different countries.
(F) Fuzzy exceptional problems