1. Longer than the founders originally thought, but in the ones that do break even or become profitable, not so long that they go under. Seriously though, it va

1. Longer than the founders originally thought, but in the ones that do break even or become profitable, not so long that they go under. Seriously though, it varies so wildly depending on factors that its' difficult to say, but if the fundamentals of the business are good then you're going to be alright. 2. Not necessarily. Sometimes they just haven't found their right way of monetisation. Facebook, Twitter, Youtube are all examples of large scale long term loss-leaders. 3. It varies from investor to investor, but generally if the company fundamentals aren't there, if the cost of recovery is greater than the cost of writing it off and if it looks like there's no way out, that would be the main alarm bells that I can think of.