I feel that design is difficult, especially when we are designing for others. Since the product is designed for the users, we have to understand their behavior. Take the example of a door in the reading: The way a hurried person interacts with the door will much different from someone who takes their time to use the door. While the first one needs to prioritize the efficiency of how the door works, the latter can be focused on the creative aspects of it.
Furthermore, it sometimes difficult to be someone’s shoes. Assume that we are designing a product for the public customer. However, because we are the product owner, we understand the product much more than anyone else outside of the product scope. There will be a lot of things that are obvious under our eyes but it serves no meaning in the users’ eyes. That is why Human Centered Design is really important. However, the human here is our application users and not ourselves.