A known entity like LOTR makes more business sense than to do something equally epic like a Wheel of Time series.
But I can argue other logic saying you need to take chances on other things and doing so will allow you to do breakout hits.
It is a question of balance and tipping points, and having faith in your "producers" (and other hollywood titles) in order to find the best seeds when the wheat and the chaffe are intermixed.
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I understand why it happens, but personally I am so tired of it.
Oh yeah I am glad I abandoned Game of Thrones midway during Season 5 and I am just waiting now for the books based off what I heard of Season 6 and 7.
Once the passion is lost in a series, you can't reawaken it by doing the same old same old, you need something new to reinvigorate the franchise and also remind you of the "child like" fanatical passion you used to have for a series.
Sorry you abandoned GOT. It's really quite good. Though this past season was very rushed. Season 6 was excellent though.
I do kind of wish though that Amazon had said Eff it and not done Epic Fantasy and instead tried to do Dune. That would have been way better I think.