In consumer software, customer acquisition cost is low and development costs can be spread over millions of people, so there is a big profit potential even though the price is low. For large enterprises, the customer acquisition cost is high (lots of meetings with suits), but the payout is high (millions of dollars is good value for software that is going to be deployed at 20,000 locations and serve millions of customers). For a small business, customer acquisition is still expensive (sales and support done personally), but the price is still pretty low.
The book cured me of mumbling "I could make software better than that in a week" every time I saw a receptionist at a small office struggling with a bad app.