One of the applications I work on has a long history of problems handling data for people with the last name Null. I've given feedback on these bugs and make se

One of the applications I work on has a long history of problems handling data for people with the last name Null. I've given feedback on these bugs and make several recommendations for fixing them, but the folks who work on the application framework just...don't care? I don't know. They certainly don't design with exceptions in mind. That's such an alien way of thinking to me. I was taught that 80% of your work is spent handling 20% of the data. Is there something cultural that prevents other programmers from working in exceptions-first mode? Maybe it's just with boring business logic. I've heard that the most robust networking applications are written assuming constant worst-case failure states. Anyone have any insight into this phenomenon? I get that there are practical limits to what you can plan for, but if you're accepting string input, shouldn't you at least be prepared for apostrophes?