This seems to be a never-ending discussion, regarding methods of
design and development. I contract to have certain system/apps that
I've designed prototyped, but certainly not all nor even the majority.
I work on wireframes, graphical layouts and keyframes, intensive
flows, and comprehensive implementation documentation, and have done
so for numerous OS GUIs (starting back in the 80s), lots of medical
equipment and devices, complex military systems, and so many mobile
device, phone, smartphone, and media players that I can't even count
them.