The field of requirements engineering for business processes has grown during the last several years. As business processes are assumed to fulfil organizational goals, goal models could be transformed into business process models that specify how business processes fulfil the organizational goals. Although both the fields of Goal-Oriented RE (GORE) and Business Process Management (BPM) received a lot of attention from researchers, the methods to transform goal models into business process models still need further research. This scientific evaluation paper analyses current methods to identify the practical challenges that need to be addressed for an effective transformation of goal models into business process models. We illustrate the dis- covered challenges using the case study of Seven-Eleven Japan. The main challenges that were discovered are a lack of responsible role, insufficient concept mappings, informality of the transformation algorithm, no full support for organisational structure and a lack of inter-model consistency checks. Our expected contribution of discovering these challenges is to lower the barriers of transferring new goal-to-process methods to industry. As we consider i* constructs the most adequate in GORE for our purposes, we limit our study to transformations that start from i* goal models.