High performance code can often be an order of magnitude longer and more complex to write than moderately performant code. When you're not even sure what you're

High performance code can often be an order of magnitude longer and more complex to write than moderately performant code. When you're not even sure what you're building yet, aiming for performance first is a waste of time and a good way to ensure you end up not realising anything at all. Optimise for what's important for your specific project. Maybe exploring the design space is the priority to start. Maybe releasing before the end of the year is more important. Not all projects are the same so it's pointless to argue about general rules like this.