The idea that torture is unreliable is an idea that is distinctly Western in origin and very recent, really just appearing when the idea of human rights started appearing.
And while I feel strongly against using torture due to moral reasons, I would argue that its effectiveness is not as unreliable as modern scholars and the news media would like us to think.
Military history is rife with accounts where information gleaned through torture was accurate and gave an advantage to the side who had done the torture.
Israeli authorities claim to have prevented over 90 attacks through information gained from torture. French general Paul Aussaresses in Algiers claimed that he was able to find bombs and locate terrorist cells through the use of torture. In 1995 the Philippines intelligence service gained information through torture that foiled an Al Qaeda plot to crash 11 airliners into the ocean and kill 4000 people.
Torture has existed in every culture in the history of mankind, since the dawn of that history.
If it were so ineffective would it have been so widespread? I do not believe so.