In the—virtually non-existent—case where you implement perfect mockups, with a flawless design system, you could do without it.
For anything else, yes you need some design notions. Even with a designer, you will need to design a few unattended corners, you will have to interpret some behavior etc. And of course, it can be your core skill to both design and implement! Simple effecient designs, implemented right away can be crazy efficient.
In the—virtually non-existent—case where you implement perfect mockups, with a flawless design system, you could do without it.
For anything else, yes you need some design notions. Even with a designer, you will need to design a few unattended corners, you will have to interpret some behavior etc. And of course, it can be your core skill to both design and implement! Simple effecient designs, implemented right away can be crazy efficient.
Couldn’t agree more!!