It is the most selfish personal need and decision that you think "right" to quite with yourself. It is just like the most poor one you come on and the most wild, barbaric one that takes you from wonderland, life, your lovely earth, rain, pets, maybe parents, grand parents, sea, home  and from main and very very important one -wishes for forever. 

This decision has some reasons. Maybe you are in depression, maybe you love your girlfriend or boyfriend more than every thing, maybe you want to taste it just for fun or interest, maybe you want to get such kind of pleasure with killing yourself, maybe you have some unsolved and insolvable problems and etc.

They are all can be seen unique and particular to your personality, but suicide decision in every part and  scene is the selfish one because of if you kill yourself now then  you will not have a chance to taste life events like making sex, eating different delicious dishes, hugging with parents, mom, friends ( I mean real one, she or he can be nobody,but especial thing just your soul and your body), traveling around world, velocipede biking under rain or summer heat, making snowman with your relatives, watching favorite movies or TV programs etc.