In e-commerce, the more shoppers Amazon lures, the more retailers and manufacturers want to sell their goods on Amazon. That gives Amazon more cash for new services—such as two-hour shipping and streaming video and music—which entice more shoppers. Similarly, the more customers use AWS, the more Amazon can invest in new services, which attract more customers. A third virtuous circle is starting to whirl around Alexa, the firm’s voice-activated assistant: as developers build services for Alexa, it becomes more useful to consumers, giving developers reason to create yet more services. So long as shareholders retain their faith in this model, Amazon’s heady valuation resembles a self-fulfilling prophecy. The company will be able to keep spending, and its spending will keep making it more powerful. Their faith is sustained by Amazon’s record. It has had its failures—its attempt to make a smartphone was a debacle. But the business is starting to crank out cash. Last year cashflow (before investment) was $16bn, more than quadruple the level five years ago. So long as shareholders retain their faith in this model, Amazon’s heady valuation resembles a self-fulfilling prophecy. The company will be able to keep spending, and its spending will keep making it more powerful. Their faith is sustained by Amazon’s record. It has had its failures—its attempt to make a smartphone was a debacle. But the business is starting to crank out cash. Last year cashflow (before investment) was $16bn, more than quadruple the level five years ago. Many of these services support Amazon’s own expansion and that of other companies. The obvious example is AWS, which powers Amazon’s operations as well as those of other firms. But Amazon also rents warehouse space to other sellers. It is building a $1.5bn air-freight hub in Kentucky. It is testing technology in stores to let consumers skip the cash register altogether, and experimenting with drone deliveries to the home. Such tools could presumably serve other customers, too. Some think that Amazon could become a new kind of utility: one that provides the infrastructure of commerce, from computing power to payments to logistics.
参考答案： 在电子商务方面，亚马逊吸引的顾客越多，就会有越多的零售商和制造商想在亚马逊上销售它们的产品。这给了亚马逊更多的现金去提供新服务，例如两小时送达以及流媒体视频和音乐，而这又吸引了更多顾客。与此类似，越多客户使用AWS，亚马逊就能在新服务上投入越多，进而吸引更多客户。第三个良性循环则是围绕该公司的语音助手Alexa展开：有了开发者为Alexa设计服务，它对消费者来说就越来越有用，开发者继而就有理由去创造更多的服务。
只要股东们对这一模式保持信心，亚马逊令人兴奋的估值就会像一个自我应验的预言。公司将可以一直花钱，而它的支出也会不断让它变得更强大。支撑股东信心的是亚马逊的业绩。它曾经失败过，制造智能手机的尝试便是个灾难。但是公司正开始大量产生现金。去年的现金流（投资前）为160亿美元，比五年前的四倍还多。
如果说亚马逊对投资时间期限的态度非同寻常，那么它对公司经营的广度也是如此。如其年报所述，公司目前以及未来可能的竞争对手包括物流公司、搜索引擎、社交网络、食品制造商和“各种各样的实体、数字和交互式媒体”的制作商。如此之广的跨度更像是一个企业集团而不是一个零售商，这愈加让亚马逊的股价看起来虚高：股市通常会对股价打一个“企业集团折扣”来反映它们的低效。
这些服务中的很多都有助于亚马逊自身和其他公司的扩张。一个明显的例子是AWS，它既为亚马逊也为其他公司的运营提供动力。不过亚马逊还向其他卖家出租仓库。它正在肯塔基州建造一个价值15亿美元的空运中心。它正在门店测试新技术，让消费者完全跳过到收银台结账的环节，它还在尝试用无人机送货到家。这些工具也很可能会服务于其他客户。有些人认为亚马逊也许会成为一种新型的公用事业，提供从云计算能力、支付到物流的商务基础设施。