No one can properly function after repeated nights of less than 4 hours of sleep. I seriously think the jail just wants to push people to misbehave so they stay there longer and the jail can reap more profits.
It's one of several measures to keep the inmates docile. See also: feeding them low-quality food, and only enough for survival.
A hungry, sleep-deprived prisoner isn't going to revolt, and after release may think twice about going back.
Sleep deprivation and malnourishment are forms of torture, and constitute human rights violations.
It's supposed to be a correctional system. How are we supposed to reduce recidivism when the system is designed to destroy lives?
Bingo. Private prisons have no incentive to reduce recidivism.
See also Shane Bauer's undercover report "My Four Months as a Private Prison Guard":
https://www.motherjones.com/politics/2016/06/cca-private-pri...
"Jail" often means a county operated facility and then at the state and federal level most prisoners are still held in publicly administered facilities.