What sort of experiences made this clear to you?
I ask because I was considering cancelling my subscription today, since it's the last day of the month, and this month I feel like I didn't really get my monies worth. They haven't sent me any new titles I want. I even tried slimming down my Game Queue just so they would be forced to send me a game, I had like 6 games with a "low" availability which they say is a 25-49% chance of shipping that day. It went multiple days without them shipping me anything, so rather than not get anything I added some older titles back into my queue and just got one of them. It's better than nothing but it is disappointing service. I've only been a member for two months consecutively.
EDIT:
I just contacted their chat support and they said it has only to do with how long the game has been in your Q (which I guess is related to seniority when you think about it, since if you put a game into your game Q as soon as it's been put into their database you're first in line for it.)
Copy of the chat log:
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Joshua P: Hi there, my name is Joshua P. I will be assisting you today.
amazinmace: hi
amazinmace: I have a question
Joshua P: Sure go for it
amazinmace: Is game availability based on seniority, like how long you've been subscribed or how long you had a game in your game Q?
Joshua P: It has nothing to do with seniority
Joshua P: It's about how long a game is in your GameQ and how long you've been without a game
amazinmace: Does unlimited PC play factor into anything?
Joshua P: No it does not
amazinmace: Ok, thanks
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