Why Islam beheaded hostages

(1)a slaughtering system
(2)The head of the animal should be directed to Mecca, and the slaughterman should shout in the name of God 1 the Great After that, you have to hit your neck deep with a very sharp knife and it has to be done in a very instant. If you start bleeding like this, you have to hang the animal upside down and wait until all the blood is gone.2
(3)Animals should not be knocked out before slaughter and should be a species permitted in Islam. There are differences of opinion, but slaughter should generally be Muslim