Why has Thumbtack been so successful?

They offer their suppliers a low-commitment way of getting on their platform-- their own web presence. After getting them on the platform in a low-commitment way they can easily get them to participate in the their marketplace with a simple up-sell. They also developed an effective marketing/sales method by hiring a team in the Philippines to call potential suppliers and offer them the web presence benefit. Also, their model of having suppliers pay to bid on a project results in more qualified options and is an easier way for most customers to find a supplier. They keep it simple for the customer.

Because of self-promotional posts like this one?