Comparator doesn't respond the execute command

I wrote a command with the fastest redstone_clock "execute @p[name=Whatever] ~ ~ ~ kill @e[type=Arrow,r=2]" and i connected it with an comparator to another command "say Hi"

So what it means is, whenever an arrow is coming straight to me, it will dissappear, and then "Hi" will show up in the chat. But I didn't see any "Hi" in the chat, and I did'nt see the comparator blinks. So, is this a bug or what? I feel confused.