Industry 4.0 and Smart Factory are associated with major changes in the industrial world. The innovative forms of networking, communication and collaboration between people, machines and products have led to a new type of production system in which information and knowledge are exchanged more quickly and efficiently. As a result, among other things, the role of cognitive assistance systems and their supporting function for employees within production processes has gained in importance, both in the training phase and in the active work phase. Especially for on-the-job learning, these assistance systems open up a wide range of opportunities. This paper focuses on the opportunities and challenges associated with the use of cognitive assistance systems for workplace learning. We discuss current research on the potential uses of these assistance systems, particularly for process accomplishment as well as for supporting specific groups of employees. Furthermore, we address the limitations for the use of these systems. At the end of the paper, we identify three focus areas for the future development of AI in industrial processes and for research on this.