Where I'm coming from: I used to take org-mode notes sometime back and push them to GitHub. Everyone told me GitHub can render org-mode, so it is going to be a great experience when I want to read my notes later and when I want to share the notes with others. But sadly the GitHub org-mode parser is terrible. Instead of just using Emacs itself to parse org-mode files, GitHub has reimplemented some half-baked org-mode parser in Ruby that breaks in all sorts of edge cases. So I can still write my org-mode notes in Emacs and review them in Emacs but I cannot really share them easily with other GitHub users as the initial claims promised it to be.