World Day Against the Death Penalty Day

On World Day Against the Death Penalty Day, i have never understood the hypocrisy of the state killing someone for killing someone because apart from being a show for other people
to hopefully act as a deterrent and satisfying a need for revenge, what does it do?
For the state to take a life as a punishment for taking a life doesn't seem a very civilised way of doing things but despite it being abolished in most continues, it still goes on and in 2017 there were 33 countries who dealt with their more unsavoury members of society by shooting, hanging, injecting or in some cases chopping their head of with a sword in the town centre.
Amnesty International have gathered together the statistics and the top state executor is China who refused to hand over the data but Amnesty consider the executed number is measured in the thousands.
The second highest state executor was Iran (507+) then Saudi Arabia (146), Iraq (125+), Pakistan (60+), Egypt (35+), Somalia (24+), USA(23) and Jordan (15). 
While 33 countries carried out executions in 2017, the Amnesty figure reflects a decline of use of the death penalty with 21 countries that did not carry out an execution despite not having abolished the death penalty.
It still means that that there are nearly five times as many countries not executing prisoners as those that still do and looking at the names of the countries on the list, some you are not surprised to see there while some you hope would be embarrassed to find themselves included with such company.