Well, so I would start my own company and run you out of business.
Well, in any case I would be the one dictating the specifications. I have not much interest in being a programmer ordered to make stupid programs...Not the point. Programmers are employed to produce stuff that works to the specifications and quality control of the employer and the quality controllers. Disaster one: allow programmers to be their own quality control.
Simple logic. What they cannot see in any way will not matter to them.You don't know. You are not the "Universal User". Tester, quality controllers and customer facing staff know better. You also can't predict what some customers may demand.
You seem to describe a parallel universe different from the one we live in. Already many decades ago dedicated chess computers were succesfully sold with the explicit instruction that using the hash table, without which it would play hundreds of Elo weaker, could occasionally lead to faulty moves or lines, and that to be really sure (e.g. when solving puzzles), you'd better run them without using hash.
So according to you chess programmers cannot use hash tables, as these would occasionally mask repetition draws. Dream on...The bottom line is to produce code that is 100% bug free under all circumstances, including a bunch of circumstances you won't have predicted. Try the School of Hard Knocks for the appropriate lesson.