Asleep At The Switch Meaning

Example : 1909, Clinton Rogers Woodruff, "Municipal Review 1907-1908," The American Journal of Sociology, vol. 14, no. 4, p. 488:  His vote demonstrates that the people of Philadelphia are not asleep at the switch, are not indifferent to their political duties.1922, P. G. Wodehouse, Right Ho, Jeeves, ch. 10:  My guardian angel had not been asleep at the switch.1974, S. D. Isard, "Review of Computer Models of Thought and Language," Science, New Series, vol. 186, no. 4164 (15 Nov.), p. 625:  It is sometimes difficult to guess whether a sentence has been garbled by the author or the typesetter. . . . In either case, the editors were asleep at the switch.2003, Donald Bartlett and James Steele, "Asleep at the Switch," Time, 13 Oct.:  Why America (but not Canada) failed to set up a needed synfuels industry.