Depends on what early-stage means. If that means no funding money, then this statement is simply not true in many cases. Suppose you're tring to sell software and support. How are you going to sell a 1-year support contract if the customer can tell there's no guarantee you'll be around in 3 months? I'm speaking from personal experience. OTOH I'm sure the situation is better for web startups that are selling a service on a monthly basis.