As Jay said, in rare cases, an update can sheep issues (whether in Discourse itself or with plugins/components).
I’ve seen it happen a couple of times in a few years. It’s very rare, and fixes are made quickly, but because of this, I tend to get information on the updates (and check the Contribute > Bug category 
) before rebuilding my instances. I often wait for a few days after a new version is officially released.
And do a ./launcher cleanup sometimes as well.
So, I prefer to update when I want and after gathering information. I have potential damage control, it’s safer.