User blog comment:DaNASCAT/Technical Update: April 10, 2017/@comment-5558012-20170411012140/@comment-126761-20170411140742

In general we'd prefer to do fewer things, better. When time and resources are limited (as they always are), making '5 things great' rather than '10 things average' can be much more helpful for everyone.

Of course, decisions are more nuanced than that - and this post is not an announcement that Achievements is being retired - but we've been doing a lot of reviews of older code recently. (There's also a lot of backend cleanup work going on that's invisible to most, but will really help us in the future. I will see about covering some of that in a future update.)