无法量化的风险Unquantifiable Risk
如今创办的许多 Web 2.0 创业公司，其风险在事先完全无法量化。这类公司大多是高度社交化的应用，需要一大群人稍微改变自己的行为、或者养成一种新行为，它们才能运转起来。这份名单包括点对点借贷、推荐物品的社交网络、新型群组通讯系统、可下载的照片分享客户端等等。虽然过去也有一些类似的模式取得了成功（尤其是 MySpace、Flickr、EBay、Skype、Craigslist），但失败的要多得多。
作为创业者去创办这类公司，问题在于：你基本上得先把用户采纳曲线爬上去，才会有理性的 VC 考虑投资你。没错，一旦做成了，这类公司能产生惊人的网络效应；但在用户采纳之前，你几乎没有任何办法量化采纳风险，因此向 VC 推销就变得非常非常困难。即使某位合伙人相信这项服务会被采纳，他也无法用任何数据说服合伙机构里的其他人。正因如此，这类公司中能拿到融资的少数，要么是因为创始人是名人，要么是因为赶上了泡沫式的投资狂热。
基本上，如果你没有过往业绩，又正在创办一家 Web 2.0 公司——它需要一群关键规模的用户去做一件迄今为止几乎没有证据表明人们在网上会做的事——那么你要么得先自力更生撑上一段时间，要么给 VC 提供一些其他可以依据的判断信号（名人创始人、核心技术研发），要么找到一位愿意相信你的个人天使投资人（说起来容易做起来难）。
反过来，那些从事硬核技术开发、价值相对确定的创业者，往往会极其羡慕社交网络/点对点领域的成功企业。后者看起来拥有牢不可破的垄断地位、有机的增长，而且没有复杂的开发需求。然而，这不过是幸存者偏差在起作用。社交/点对点类业务彻底失败的概率要高得多，这一点仅靠看赢家是看不出来的。
A lot of the Web 2.0 startups getting started these days are of the variety where their risk is completely unquantifiable a priori. Mostly, these are highly social applications which require a large group of people to change their behavior slightly or to adopt a new behavior to work. The list includes peer-to-peer lending, social networks for recommending things, new group communication systems, downloadable photo sharing clients, etc. While some similar schemes have worked in the past (notably, MySpace, Flickr, EBay, Skype, Craigslist), the set that have failed are much much larger.
The problem with starting one of these businesses as an entrepreneur is that you basically have to get up the adoption curve before any rational VC will think about investing in you. Sure, if it works out, these businesses can have phenomenal network effects, but in advance of user adoption, it is nearly impossible to quantify the adoption risk in any way, and so it becomes a very very hard sell to VCs. Even if one partner believes that service will be adopted, he / she cannot convince the rest of the partnership with any data. As such, the few of these kinds of companies that get funded tend to either get funded because of a celebrity entrepreneur, or because of bubble-investing mania.
Basically, if you don’t have a track record and are starting a Web 2.0 company which requires a critical mass of users to do something that there is little evidence of people on the web doing to date, then you’re either going to have to bootstrap it for a while, give VCs some other proxy to go on (celebrity entrepreneur, core technology development), or find an individual angel who believes (easier said than done).
The flip side of this is that entrepreneurs who are doing hard-core technology development with relatively deterministic value tend to look at the successful businesses in social networks / P2P with tremendous envy. The latter seem to have unbreakable monopolies, organic growth, and no complex development requirements. However, this is just survivor bias at work. The odds of complete failure in the social / P2P businesses is much higher, which is not obvious just by looking at the winners.