I think there numbers are large because of two things: 1. People are not aware that there are so many services already. It's not enough to google for "website

I think there numbers are large because of two things: 1. People are not aware that there are so many services already. It's not enough to google for "website monitoring" to get the entire picture. 2. Entrepreneurs think that such service is a piece of cake to implement and to maintain. But the first 50 customers verify that wrong assumption. Plus, with that numerous competition, led by a few giants (like Pingdom with 700,000+ customers), it's very hard to get noticed.