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It's the most unique to pay people to sort through bad content and find good content and order it from best to worst.

First it's the easiest way to earn crypto currency. There is no other way for a common person to give a scarce resource ( his attention) and get crypto.( I would put crowd funding, not blogging as #2).

2nd it's a game. Finding and voting for something first is fun. The curation rewards are your score.

Third It's a business. It's almost like investing in a post except you are an activist and can drive traffic, resteem, or promote your investment.

Now other sites pay writers. Or maybe they facilitate payments through advertising. There are lots of ways to pay but it's not much different than a site that advertises and pays its users in bitcoin. This has been done lots of times and the sites paying the most will win and the ones with the most revenue will pay the most. A startup might win if it dominates a niche but most will fail.

For curation benefits there are no competitors. Maybe Reddit which uses moderators and votes but they aren't paying them and all votes are equal. The curation plus power function makes this unique. ( though I would say should be less than 2)

don't cut curation!

It's the most unique to pay people to sort through bad content and find good content and order it from best to worst.

Upvoting good content is a natural behavior, users will do it regardless of the incentive. The fact that users assign real money to content and that they have a limited amount of it guarantees that only the best content will be upvoted.

First it's the easiest way to earn crypto currency. There is no other way for a common person to give a scarce resource ( his attention) and get crypto.( I would put crowd funding, not blogging as #2).

The easiest way is to post content, most newbies have no clue about curation rewards and how it works.

2nd it's a game. Finding and voting for something first is fun. The curation rewards are your score.

The game is rigged by bots. I also use a bot and one week i decided to do a little experiment by manually voting instead, my curation score dropped a lot. The very large majority of curators are just subscribed to bots.
Also curators are encouraged to vote fast, this creates a situation where everyone upvote without reading any content, even manual curators they have no choice but upvote blindly.

Third It's a business. It's almost like investing in a post except you are an activist and can drive traffic, resteem, or promote your investment.

More like lobbying

the sites paying the most will win and the ones with the most revenue will pay the most.

What better way to do that than increasing demand for steem..

Now other sites pay writers.

Which sites?