Why “Just Build It Yourself” May Be the Most Expensive Sentence in Business There is a version of this argument that visits almost every ambitious founder sooner or later. It usually arrives late at night, just after another software invoice has landed in the inbox. Why am I paying this company every month for a tool that reconciles invoices and calculates GST? I could hire an engineer, build the same thing once, and own it. Their margin would stay on my balance sheet instead