Wikisource's inclusion policy, a critical part of the recent infrastructural development, was recently written and proposed. For the many years that Wikisource has been in existence, the policy concerning what Wikisource does and does not accept was fully explained. As such, new contributors always approached the project with slight confusion regarding whether their additions would be allowed.
Now, experienced contributors no longer need to go into long explanations regarding what is and is not acceptable and can simply direct the editor to the policy page. Also, a formalised version of this policy will help editors engaged in inclusion disputes as the rules will clearly explain acceptable content.
The current draft is still in its discussion phase and will undergo more community discussion and revision before being implemented across the project.