It’s a classic problem of scale. When a company works on several projects simultaneously, it faces a number of difficulties when it comes to continuous integration services.
Running your own CI setup on the cloud is expensive, and the way you are charged can often seem unreasonable — the server is used only for a few hours, but you pay for it as if you were using it all day long.
Building your own data-center is even more expensive than that. It’s not just the computing and storage, hosting your own CI chain: projects have to be configured, test servers need to be created and monitored, packages need to be upgraded. It takes a lot of time and effort to keep it all running. And whatever you do, you’ll inevitably have your developers asking you to increase the number of instances dedicated to continuous integration.