Depends a lot on what sort of software you're building. A lot of code has complex requirements and simple implementations, but the opposite definitely happens

Depends a lot on what sort of software you're building. A lot of code has complex requirements and simple implementations, but the opposite definitely happens too. Rarely in risk-averse business environments, but in R&D-adjacent work it's common. You can have straightforward requirements (e.g. "return true if the provided HTML code is a blog post"). The difficult part is discovering a means of satisfying the requirement.