Rylai's not a good item on kass?

In my every game of kass, I go > > > , + one defensive items

The first three as must buy items

and flexible on other three of them .

I don't know what happened , but it seems no one go anymore

provide lots of slow with ability , make him much easier to chase enemy with ult

and provide the AP and HP seems the perfect match of kass

But why no one pick now?

thank you for answering