Yeah I agree. I basically wrote this blog out of my challenges learning this content. It involved a lot of code spellunking and trial and error to figure out precisely what these concepts meant. I do find Beam powerful, but also to be a bit esoteric at times and difficult to follow how watermarks, windows, and triggers all work. And we encounter sometimes unexpected behavior that frequently causes us to revise our understanding of these concepts.

There's a fair amount of Stackoverflow highly voted answers out there like "I dunno, try this trigger, see if it works" without much understanding of how everything work underneath. Probably cause it's tricky to grok

This seems to be a general problem with many projects under the Apache Software Foundation. You look at the landing page and end up not figuring out what the project is or what it's for. This seems to be especially true with projects in the whole "big data"/"stream processing" sphere.

Author here, thanks. I'll get it fixed.