Comment by olafmol

I'd like to point out that CircleCI is typically faster (and more consistent) than GH Actions, and also offers a free tier (with more free build credits for opensource projects: https://circleci.com/open-source/)

Personally I believe that GH Actions' adoption was mostly a case of "we already use github as our VCS, so we get Actions for free with our MS licenses" combined with "hey, we can easily use all those Actions that people put online" (with all the security and compliancy issues that come with such a YOLO mindset lol)

(Disclaimer: i work for CircleCI)