These providers are wearing a very large cost base per customer, but getting very little revenue in return.

这些供应商承担的单位用户成本基数太大，收入太少。

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As a result, the company achieved a 30% lower cost per acquisition than other platforms and saw a 6x return on advertising spend .

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But most people look for a handset subsidy: a lower upfront cost for getting the phone in return for paying some set fee per month over the life of the contract.

FORBES: Apple's iPhone Just Isn't Worth It

Bookstores return about thirty-five per cent of the hardcovers they buy, and publishers write off the cost of producing those books.

NEWYORKER: Publish or Perish