Akali's Q

First of all i wanted to start by saying that i'm not too sure about her mechanic. Does her Q have a cast time, if so, why? She's supposed to be a ninja is she not? so why does her Q have a cast time? I've noticed that it has been feeling pretty clunky to use at the moment for one reason or another, and will at times be constantly spamming Q while NOT being stunned i might add, and the actual animation/ability not going off.