Rehabilitation theories present however the following deficiencies:
First, there is no sound scientific research to determine how different individuals react to the same rehabilitating methods.
Second, rehabilitation may depend more decisively on the individual psychological background, hence on his particular motives to commit crimes, than on the rehabilitating methods or philosophy.
Third, a rehabilitation program may prove to be too costly and complex to be successfully implemented and utilized in most countries.
Finally, rehabilitation must refer to the sociological findings on the socialization and resocialization processes, as change in lifelong socially acquired patterns of behavior and values entails a much more complex – and sometime traumatic – change on the individual's structure of character.