This study addresses the question “How do Software-as-a-Service (SaaS) vendors enhance their software with insufficient domain knowledge?” Results were obtained by analyzing a dataset from a SaaS vendor that provides administrative software to small schools around the world. The dataset includes archived data (email messages, company documents, and Skype messages) and access to the company’s online repositories (sales pipeline, client online chats, and engineering repository). We identified three types of domain knowledge that are relevant to SaaS vendors – organization specific, industry-wide, and regional variation. We also generated six propositions explaining how industry-wide and regional variation knowledge influences the SaaS enhancement process, and at which points in the process these two types of domain knowledge come into play. This study refines our current knowledge by highlighting the unfolding stages between insufficient levels of domain knowledge and software enhancement outcomes.