@Sammysees people being released very often go to a hostel, where they have more freedom than in prison, but still have to follow certain restrictions.
This is particularly so in the case of violent prisoners, released on licence after murder or manslaughter charges.
If they then fail to cope with this, it's easier to recall them to prison quickly.
There was a tragic case in Scotland recently, where a murderer was released like this, and as soon as he was allowed out for the day, he followed a woman and killed her.
Addicts often need to be in places where they can be observed and tested, too.
It's not a case of opening the prison gates and letting dangerous people out back to the bosom of their families. The public still needs to be protected.