These documents all look very smart, but how does anyone have any idea whether the numbers in them are even close to realistic? I can make up some cute hockey stick numbers for any of my businesses, but why should anyone trust them? Particularly for businesses that <i>haven't even launched yet</i> and therefore have <i>literally zero</i> hard data on whether customers will actually pay them money or how much or for how long. How many startups in that position, with no financial data and no evidence of product-market fit, can credibly predict even a year ahead that they won't pivot to some completely different plan, never mind 3 or 5 years out?<p>When I started my first B2C, a long time ago now, it was actually the bank where we opened our business account who asked these kinds of questions. We sat down, put our best guesses at plausible numbers into a spreadsheet for things like acquisitions and churn, worked out the money that would result.<p>Barely any of the key assumptions we made were within an order of magnitude of reality, and they were <i>all</i> in the wrong direction. For example, we have far higher churn than any example startup business plan I have ever seen just from card charges that fail with no obvious explanation each month where we don't subsequently recover and continue that subscription. That problem remains one of our biggest pain points to this day, and that effect alone has turned many an otherwise profitable month negative and reduced that business to a fraction of the size it would otherwise have been by now if everything else was held constant. No-one here saw that coming. No example plans or startup guides or financial advisors we consulted even mentioned the possibility, never mind giving any concrete figures for what we might expect.