It is going to come down to context. For the most part, you never know quite what it is you are designing, so an iterative approach to design with fast feedback

It is going to come down to context. For the most part, you never know quite what it is you are designing, so an iterative approach to design with fast feedback cycles will get you there quicker. Give people something to play with, see how they use it, and continue from there. But sometimes you need to know what is you are designing before giving it to people, because there are large risks associated with improvising. In those cases, making The Right Thing is still expensive, but it may reduce the risk of catastrophe. I think, however, that the latter cases are rarer than most people think. There are ways of safely experimenting even in high-risk domains, and I believe doing so ultimately lowers the risk even more than doing The Right Thing from the start. Because even if we think we can spend years nailing the requirements for something down, there are always things we didn't think of but which operational experience can tell us quickly.