So imagine you're a young jobseeker, just starting out on your journey and you are trying to learn about what employees have said about a company you are wanting to apply for. You see that glassdoor has plenty of reviews on them, but as soon as you try to view them it completely blocks you and tells you to contribute your own review in order to see them. However if you've literally never worked anywhere you cannot damn well review anywhere now can you, and therefore you cannot actually use this website, so don't even bother. I actually assume they're doing this to mine as much data as possible, otherwise they'd let you in and simply ask you to contribute your own, when you've got one, because it would be a good thing to do.