The main issue is that students don't have original ideas, at least not way into their master's project. This means that every single thing they write througho

The main issue is that students don't have original ideas, at least not way into their master's project. This means that every single thing they write throughout their studies is some regurgitation of stuff they find elsewhere. To avoid having a reference after every single sentence, we need to allow them to pretend that some of the stuff they read is common knowledge, and can thus be passed on as such, without reference. But if someone else actually wrote the sentence, that would be plagiarism, hence writing it in your own words.