Con: You may not be able to handle or even estimate the technical/infrastructural/administrative debt involved in interfacing with what the cloud you're using _

Con: You may not be able to handle or even estimate the technical/infrastructural/administrative debt involved in interfacing with what the cloud you're using _becomes_ over time. Others' clouds can thus turn your future into more of a black box, especially if your project is e.g. non-enterprise and yet operating in an enterprise cloud environment. Pro: You usually don't need to reinvent as many wheels, and this is generally more true the more the cloud and its userbase align with you and your needs. Clouds are also generally set up to cater to different forms of opportunistic development or opportunistic project spin-ups, which is a similar sort of advantage.