Why do people say alistar scales well?

he blows, his cooldowns are ridicolous

Because Alistar is a type of champion that scales good into the late game because of his abilities instead of his stats. He has two super peeling abilities, and his ultimate can easily be used to run down the enemy without having the fear of actually having a realistic death until ult is down. The healing is someting that can be neglected but it also applies a slow with Rylais, technically speaking he is a much better pick for adc's without gap closers or mobility such as ashe because he can keep most threats away by himself.

TL;DR: Stats do not equal good late game scaling.

He's in a pretty bad spot after his multiple ratio nerfs. Pure durability damage soak is the only thing he can really do anymore.

I wish his heal wasnt so crap tastic

Alistar with Cool Down Reduction is scary. With 40%, you can activate his Q every 8 or seconds, W every 6 seconds, E every 7.2 seconds, and R is very active.