The reason this is complicated is that the burn rate of the business is determined its net margin (NM) and the viability of the business is determined by its co

The reason this is complicated is that the burn rate of the business is determined its net margin (NM) and the viability of the business is determined by its contribution margin (CM) (NB I didn't say gross margin - they are slightly different). CM is extremely hard to calculate because "fixed" costs - in practice - do scale with the number of customers. But on the other hand, if you have a positive CM, it may make sense to invest heavily in capacity, leading to negative NM.