You can’t swing a ledger without bumping into a SaaS solution anymore. SaaS (software as a service) has slowly taken over as the preferred way for companies to scale while not having to make huge internal investments in equipment and human resources.
The upside of doing it yourself is that you get to have total control. The downside of doing it yourself is that you have total responsibility for it 24/7.
The biggest reason much of corporate America is moving to a cloud-based, SaaS solution for so many of their systems is that it allows them to concentrate more on their core business, and let best-of-breed software companies support them.
For banks specifically, the idea of having a team of software developers, ux designers and developers, software architects, database administrators and support for every piece of technology in use can quickly turn your banking organization into a software company that just happens to specialize in banking applications.