This also applies to any kind of on-line system that works like Netflix does, with a queue that prioritizes requests.
When you share a Netflix account with one or more people,
1) Requests are first-come, first-serve. You may not 'jump the queue' with your request unless you have the express agreement of all parties that the new request has priority.
2) Do not claim ignorance when someone calls you on the queue jumping. You can say "Oh, I'm sorry, I was just so excited about this movie, I really wanted to see it right away!" You should not say, "Oh, I didn't know I was pushing your stuff down in priority". Yes you did, because it takes a separate step to promote a movie to first position which, by definition, pushes everything else down a step.
3) You may not delete requests made by other people nor demote those requests, no matter how little interest you have in it.
4) You may not stack the deck by filling the queue with all of your requests at once. Movies will still be there next month. Give other people a chance to get a request in edge-wise. If no one else is putting stuff in the queue, over time you'll get your movies anyway. Just don't do it all at once.