Make It Rain is getting nerfed?

Based on what was said earlier, I was expecting usability improvements to Make It Rain. Like a quicker startup time or shorter cast. Certainly not...nerfs.

Make It Rain has never been about the damage (unless you're playing her AP lol). It's about the slow. It's the only CC she has, but it's a strong slowing field. It's a great tool to cut off escape routes or prevent enemies from chasing. But the duration is getting shortened? This is certainly a nerf. It also gives vision, so the vision duration is being reduced as well. Additionally, it sounds like the rank 1 slow is increasing in exchange for decreasing the max rank slow. This is also a nerf as far as I'm concerned. I always maxed it first because the slow is so strong, and there's very little incentive to rank up W. (Now it probabably going to be better to max it second and Q first, but this is still a nerf to max rank)

So why. Why? Why does this skill need to be nerfed? A marksman with poor mobility is getting her only CC nerfed. I don't understand.