Their algorithm needs to balance the cost of heavy users against the cost of negative press. Remember "No Late Fees." I'm sure they're thinking about it. Then again, this opens an opportunity for those with deep pockets to eat NF's lunch.
I cancelled about a year after they started. I was moving and just didn't have time to watch. At that time it was $19 for four movies, and I was a short drive from their San Jose office. Next day turnaround. Later they bumped the price and dropped the allowance, and Hollywood kept sending me 99cent rental coupons. Never signed up again.
It's interesting to watch the business (and competition) develop. I liked it when it worked. (Except for the broken Ronin discs they kept sending. A warehouse forklift operator must have cut that apex too close.

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