That's a stupidly incompetent way of doing software development.

If the people upstream are fucking professionals then it would be very rare than the edge cases are discovered at the coding stage since that shit can baloon into massive rewrites and even redesigns (if, for example, it impacts throught to multiple system tiers) which in turn means productivity is shit and the resulting system is a big fucking bug-riddled unreliable mess because of all the going back and all the hacking of "unexpected" (but totally expected if people did their fucking jobs) things into the existing design.

Further, the constantly ping-ponging of questions up and down the layers during development (especially if at the other end there are business user for whom the software is being made) adds a ton of overhead, not to mention needless waiting periods.

I bet you never worked with a Technical or Business Analyst or even in a project managed by somebody who was not a reactive "shoot from the hip" manager.

PS: And, yeah, I'm pissed off just thinking about that crap, because in my career I had to learn the fucking job of Project Manager, Technical Analyst and even Business Analyst after I figured out A LOT of the unecessary problems, blown up deadlines and stress I was getting at the systems design and software design levels were the product of that part of the work not being properly done or at all, so that shit you're describing as if that was the normal way of doing software development really makes my blood boil - by my professional standards that shite is amateur hour, every hour of the day, every day of the month, every month of the year.