Does rehabilitation works on prisoners today?

The word "rehabilitation" is defined as to restore a person back into a normal condition or life. Rehabilitation are used on prisoners to allow them to reintegrate back into the society or into a normal life. However the question is about the ways the Law used to implement rehabilitation, the justice system may used harsh punishments such as caning and manual labour,or "soft" ways of rehabilitation,rather than punishment, such as counselling.
The objectives of harsh punishments may be to inflict pain onto the prisoners as a penalty to their offences, hoping that these prisoners will refrain from repeating their crimes, unless they wanted to suffer the painful consequences of their crimes again. The harsh punishments also act as a deterrence to the society to warn people against committing the same crimes. However, inflicting physical pain on prisoners may not necessary means that the psychological side of the prisoners changed because they do not want to suffer the punishment again, but this is just an assumption. Prisoners with psychological problems may have trouble refraining from committing certain crimes such as theft, drug abuse, and even rape. So the infliction of physical pain or the shame from doing public work as the "chain gang" via the implementation of harsh punishments will not prevent them from committing the same crimes again.
Prisoners who commit crimes due to psychological problems ,such as being abused at a young age, will get a greater help from rehabilitation that tackles these prisoners' psychological problems rather than using physical pain as a reminder for these offenders to stop committing crimes.Undergoing psychological rehabilitation, prisoners will be able to get a better understanding of their problems and with psychological therapy,it will make it easier for these prisoners to gain greater mental strength in vanquishing their psychological problems.However the drawback of this form of rehabilitation is how long will prisoners undergoing psychological rehabilitation will forget about their psychological problems. Thus the psychological help may not be permanent while the infliction of physical pain may leave permanents scars on the flesh of prisoners or the psychological scars from the shame in doing public labour, in hope that these scars will remind prisoners for life that the consequences of committing crimes are extremely painful or degrading. Also, psychological rehabilitation may not deter others from committing these crimes as they know they will not suffer any shame or pain from committing the crimes.
Thus the justice system will have to understand the conditions of the prisoner awaiting the sentence, and assign the "most suitable" penalty upon the prisoner, hoping that the sentence will be able to both deter the public from committing crimes, yet able to prevent prisoners from committing any crimes again.