Design is a very broad topic. When I read the title, I thought it meant software system design, whether for backend or front-end or scientific computing or any other domain.
As a person who cares a lot about taking a craftsmanship-first approach to business software, and in fact I believe this for cost-effectiveness and speed-of-delivery reasons such as discussed in Peopleware, my biggest question about design is:
How do you get product managers, business managers and executives to understand that by caring sincerely about first-principles craftsmanship and design and by creating policies in which managers and executives give up their ability to supersede craftsmanship with short-term or reactionary thinking, the business outcomes and customer satisfaction, even in the short term, are likely to be better, and especially compounded over time?
I'm not saying to take an ivory tower approach and try to build a "perfect" system before you ever start testing it in the market or analyzing how customers react to it.
But I am talking about the way that important work for the sake of extensibility and maintainability, or important aesthetic judgments from engineers who have experience with what features succeed in businesses, often get superseded for poorly thought out and reactionary short-term business goals, leading to wasted effort when sprint work gets deprioritized midweek and everyone has to pivot onto poorly articulated new goals all of a sudden (and then it happens again two weeks later, and again, and again).
If management took a constrained design approach, and bought into the idea that engineering aesthetics are a legitimate reason for teams to turn around and say 'no' when they are asked to engage in an obviously dumb pivot that wastes resources on unfinished work and context switches, I believe the evidence (written about widely, e.g. even just start by reading Peopleware) shows it would lead to better results even in terms of the outcomes that the managers and executives want.
Overall it makes me feel like other questions about design are just not important unless you work for bosses who happen to "just get it" and think in this quality-oriented way. Otherwise, you can learn all kinds of cool things about design ideas, you can hire great people to advise on prototypes and design approaches, and it all just goes in the trash can because of short term, reactionary management practices.
