Most of the conventional wisdom about SaaS is spread by (marketing departments of) the SaaS companies themselves, who have noticed that the lifetime value of a

Most of the conventional wisdom about SaaS is spread by (marketing departments of) the SaaS companies themselves, who have noticed that the lifetime value of a customer is higher if they pay you every month (ideally with some form of lock-in) than if they pay you once for a program they can keep using without extra payments. If the customer is a startup themselves and therefore has a very short expected lifespan, this does not necessarily matter because the lower upfront cost enables cheaper experimentation and pivoting. If you are in a business with product/market fit that has been around for some time already, the lowest possible upfront cost is much less of an issue compared to the total cost of ownership and the risk of a critical dependency disappearing. SaaS startups do poorly on both of those metrics.