"N8N" wrote in message
...

She called me on her cell phone to tell me
her land line wasn't working again. Now explain to me how the land
line is more reliable.

Land lines are reliable because they are powered by the
nearest relay station, not the household electric supply,
thus function OK during local power outages. Of course
they are wholly reliable only with a wired connection.
Cordless phones fail during local outages (because
they need household current to maintain the base
station.) The OP did not say whether the mother uses
a reliable wired phone or a vulnerable cordless phone.

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)