Computational workflows consist of a series of steps in which data is generated, manipulated, analysed and transformed. Researchers use tools and techniques to capture the provenance associated with the data to aid reproducibility. The metadata collected not only helps in reproducing the computation but also aids in comparing the original and reproduced computations. In this paper, we present an approach, "Why-Diff", to analyse the difference between two related computations by changing the artifacts and how the existing tools "YesWorkflow" and "NoWorkflow" record the changed artifacts.