Polymer coatings find use in a wide range of industrial applications, from conventional paints and coatings in building and construction to the pharmaceutical industry, organic solar cell production, and lithium battery technology. Despite their importance, there are gaps in our understanding of the drying process, the stress development during drying, and their influence on the final mechanical properties of the dried film. This perspective focuses on the fundamental aspects of the drying and film formation process, highlights the gaps, and suggests directions for future work.