Previous 4 of 4 IA, Usability Next  Interface Design > PLI Usability Test PLI had a powerful database with thousands of products, but a set of static pages stood between the user and their goal. I diagramed this task to show the client how users had trouble on the site. The green shows a path that would satisfy the task, given that the user had prior knowledge of the site designers' intentions. The red path shows one of the many different results we got for the same task.