Eh, there's a gray area here. Your priorities really depend on the type of project you're making. Let's say you're building a web app for a SaaS business. Woul

Eh, there's a gray area here. Your priorities really depend on the type of project you're making. Let's say you're building a web app for a SaaS business. Wouldn't it be more important to make your code refactorable and develop features quickly? If you spend lots of time on [Feature X]'s performance and customers turn out to _not use_ [Feature X], you've just wasted your time and money — basically your runway, your livelihood. Basically, if a feature isn't worth making, is it worth making well? :) Maybe this is good advice if you're working on a different type of project though.