<i>When your product goes viral, yes, you do a big spike in users. But what you’re really getting is an Invasion of Looky-Loos, low quality users who come in, check things out, but don’t stick.</i><p>Charging money is the simplest thing that might solve this problem...assuming the goal of your sales funnel is closing...i.e. assuming the goal of your sales funnel is sales.<p>If you aren't focused on closing, then you never get meaningful experience at closing. It is more comfortable to defer closing and imagine that someday you will close if only.<p>There are business models where user numbers matter...Google and Facebook come to mind. But they still close their customers -- they close advertisers. Imagine Apple optimizing for users and not sales...giving away iPhones and deferring sales and revenue to some nebulous future. Sales focus is probably the only aspect of your business that it makes sense to model on Apple.