Because maybe you don't want it to kill someone as soon as they touch it.
Also couldn't it be used so if the person is touching it when they are killed something happens? So in that case if a person is touching a brick and someone kills them something could happen.
Use variables for it. Something like
plate that is touched by player:
0 || onPlayerTouch > Brick > SetVaraible | brick | 0 | dead
400 || onPlayerTouch > Brick > SetVaraible | brick | 1 | dead
0 || onPlayerTouch > self > Cancel events
Brick:
(might wish to activate it's self some how
0 || onRelay > self > fire relay
0 || onRelay > self > ifVariable | brick | equal to | 1 | dead
0 || variableTrue > [EVENTS HERE]