If your business-critical systems rely on SAAS that doesn't have a solid SLA and breach-of-contract provisions that more than cover the damages in the event, you've made "a risky decision that can tank [your] business overnight".

If the software your business depends on can't run indefinitely without getting permission to operate from someone else's systems, then you're perpetually at risk of someone else tanking your business because they decided that you can no longer use that software.