The private prisons have an interest in filling beds. That is where the money is. They don't get money by reducing recidivism, or providing job training, or providing preventative and maintenance health care (dentists to fill cavities so that the person doesn't need to get a root canal when they're released and then runs out of money on medical bills...)
Whats more, like stadiums and cities (the city paying the difference if there isn't enough attendance), there are private prisons that have a "lockup quota" ( https://www.prisonlegalnews.org/news/2015/jul/31/report-find... | http://www.njjn.org/uploads/digital-library/Criminal-Lockup-... ) where the state pays for the bed be it full or empty.
This is part of the contract, and officials making short sighted deals that have the appearance of reducing costs while actually raising them in the long term is a oft heard refrain.
I have difficulty believing that any private, for profit company would be working to negatively impact its bottom line. While it is possible that there are places where improvements in efficiency over government run facilities can be had, at the end of the day the duty of the company is to the shareholders ( CXW - https://en.wikipedia.org/wiki/CoreCivic , GEO https://en.wikipedia.org/wiki/GEO_Group ) rather than to the taxpayers of a state.
https://globenewswire.com/news-release/2016/08/23/866325/0/e...
> Specifically, Defendants made false and/or misleading statements and/or failed to disclose that: (i) CCA’s facilities lacked adequate safety and security standards and were less efficient at offering correctional services than the Federal Bureau of Prisons’ (“BOP”) facilities; (ii) CCA’s rehabilitative services for inmates were less effective than those provided by BOP; (iii) consequently, the U.S. Department of Justice (“DOJ”) was unlikely to renew and/or extend its contracts with CCA; and (iv) as a result of the foregoing, CCA’s public statements were materially false and misleading at all relevant times.
The profit motive for a private prison has shown in the past that in the interest in short term gains they will understaff and cut back on programs. Give them everyone who has been incarcerated before and they'll take the profits they've gotten and close that franchise. Furthermore, the lobbying efforts of private companies creates odd incentives in writing laws and negotiating contracts compared to facilities run and maintained by state or federal workers.