It doesn’t make sense, people who commit those type of offences where there is no doubt at all about their guilt, should be beaten to death in my opinion. Same for child molesters where guilt is proven without any doubt. Instead of that they are put to live comfortably with good food, and some are even better off than when they were outside.
Trouble is they are very different circumstances.
If someone attacks/beheads/dismembers in an clear "terrorist" act someone then they should simply be shot dead on sight. If there is any ambiguity, such as self defence, then the judicial process is the correct approach.
Whilst I agree entirely re child sex offenders, you have to be very careful that there is actual intent rather than simply an unfounded allegation. Only once that has been established to an undisputable level, then, absolutely some form of terminal event is completely appropriate.
Whilst being an advocate of the death penalty, I do believe that the process should be swift and instant rather than slow and drawn out, however tempting this might be. This isn't out of some leftie humanist sympathy, but rather that torture for its own sake, serves no use and should have no place in the punishment process.