Should the death penalty be banned in Japan?

There have been a lot of discussion and debates about the death penalty. I think that the death penalty be banned in Japan agree for the following three reasons.
Firstly people who are given the death penalty should live to pay his debt of their fault by himself.

For example they don't have a chance to pay anything if they die. Although they die, there is no benefit for anyone.

During their remaining life they should work hard to recover their debt.

Secondly technologies should not be used for killing humans.

For example technologies can make people wealthy and happy. The technology which is for killing human is not useable for anything. 

Technology should be used for the wealthy for people.

Thirdly, the cost of the death penalty is high.

For example we need the cost for proceeding the death penalty. A death person cann't make anything for the economy.

It's not free to doing the death penalty.

In conclusion,For above mentioned three reasons , I agree this theme.