Division by zero

Mathematical correctness doesn't matter here because division by zero is undefined. You can literally make it anything you want - and I've seen math professors do so as an esoteric joke. However, programmers do not like non-deterministic error states. Pony makes the outcome deterministic, regardless of hardware traps that may or may not exist, allowing for a simple error check state across all architectures which the programmer can define as fatal or non-fatal depending on their program logic then handle it accordingly.

Given the alternatives, I'd much rather have a 'mathematically incorrect' deterministic result that I can take to the bank rather than depending on disparate architectural dependent error states that are really just as mathematically arbitrary as assigning X/0 == 0 but a lot more messy to deal with.