Someone Else's Computer, Software and Storage
SaaS is always a risky proposition for any organisation because you never know whether you will be able to continue to use the service tomorrow or even get your data back when you need it.
However, organisation generally only learn, if ever, when they get caught up in an extinction level event. If your organisation is big enough, then you probably can bribe your way through government to be bailed out. Others will just wither away.