Clarity?

So to start I know that this isn't a problem for most people, but for me I see it as a problem. The question I have, is why gets a burst of movement speed if she throws her Q into thin air?

At least when I play I have to utilize her passive in that I NEED to hit enemy champions with abilities to be able to kite better. But ? No. she gets to throw her Q into a lone bush and suddenly is favored by the gods to bless her with a burst of movement speed. How is it that I can't outrun an as just because I missed an ability and don't get movement speed, but when she misses her Q she has suddenly caught up?

I feel as though this needs to be looked at.