The original motivation was to permit implementations to do the reasonable, friendly thing, and trap whenever the program dereferences a null pointer. Since C c

The original motivation was to permit implementations to do the reasonable, friendly thing, and trap whenever the program dereferences a null pointer. Since C compilers want to reorder or elide memory accesses, you can't really define explicit semantics for that (e.g. you want it to be ok to move the memory access before or after a sequence point) - the JVM has to do a lot of work to ensure that it throws NullPointerException at the correct point when it happens, and this slows down all programs even though no-one sane has their program intentionally trigger one. But the intention was to permit Java-like behaviour where your code would crash with a specific error immediately-ish, maybe not on the exact line where you dereferenced null but close to it. Ironically compiler writers then took that standard and used it to do the exact opposite, making null dereference far more dangerous than even just unconditionally reading memory address 0.