One hypothesis we pursued while designing the interview was that complexity is positively correlated with development timeline, meaning the more complex the product, the longer it takes to create. In literature, product or engineering complexity is usually defined by breaking the concept into key dimensions or metrics, for example, complexity based on size, component count, interfaces, control, assembly, etc. . In this work, we designed a set of questions for interviewees to gather key complexity parameters adopted from literature and supplemented to target our specific hypothesis. The complexity parameters and literature used are described in detail within S1. In Fig. , we plot complexity parameters against prototyping times with ordinary least squares (OLS) regression trend lines.