Companies move their applications to the cloud for two main reasons. They may have a distributed workforce want to simply access for their employees. It’s much easier to supply them with a computer and an internet connection that having to setup and maintain their application and database servers and then have to create and manage an infrastructure to enable secure access.
Others just want to put the responsibility off to another company to maintain their application and backup their data. The software companies love it because they get a consistent monthly revenue stream they can count on. Their support tasks get easier and often client satisfaction increases because the software works like it should and is always up to date.