There is a question I pondered about for a long while. What would make an easier project: A simple interaction with a complex work domain OR a complex interaction with a simple work domain?
A project with a complex interaction and simple work domain can be challenging because it involves more attention to designing with user preferences in mind. It can be difficult to sell the product well since there are many other excellent products in competition that have the same functionalities (ie, microwaves). With many other products to compete with and many types of users to please, it’s difficult to decide the best way to design the product.
Projects with a focus on simple interaction with a complex work domain relies less on user preferences but can be challenging as well. It focuses on making the interaction easier between the user and the product. There is deeper thought involved in creating the internal system, which users will not be able to see. While it sounds complicated, experts with the skill to develop the internal system are likely to be working on the project. Assuming that the experts are able to develop a reliable internal system complexity workflow, making the interaction simpler for users would be the difficult part.
In the end I think it depends on the type of project and the people who are working on the project.