How business processes as services (BPaaS) can increase the threat surface

In 400 words or more, how business processes as services (BPaaS) can increase the threat surface. This discussion is about business process as a service and security.
Most of us are familiar with SaaS, PaaS, IaaS, etc. Discuss BPaaS. Consider how business processes as services can increase the threat surface.

Use at least three sources. Include at least 3 quotes from your sources enclosed in quotation marks and cited in-line by reference to your reference list. Example: “words you copied” (citation) These quotes should be one full sentence not altered or paraphrased. Cite your sources using APA format. Use the quotes in your paragraphs.