Clarification: none of these were achievements rejected by GitHub, simply humorous ideas from a developer known as "flet" with no affiliation to GitHub.
Not very obvious considering some of the comments in this thread.
Some people are reading the title of the post as if GitHub had received proposals from their employees to include some of these achivements into the final feature set, and then decided to reject them, but the reality is that none of them were proposed by any GitHub employee at all. They are all “joke submissions” from the development community, making fun of the gamification of the platform.
Congrats on earning the "Adding Value" achievement:
Pointing out something obvious, then having someone else point out that what you pointed out is obvious, then defending the obvious thing that you pointed out by stating that it in fact is not obvious
