Maybe, but using static types is not a panacea either. It only make it easier to assume that someone have correctly constructed the value and that all manipulation have been correct so far. The type checker helps by checking that if the assumption is true, everything down the line is also true. But only in the context of the code, not in the context of the process itself, where the assumption may be incorrect, or the chain is broken somewhere due to bad logic (that’s when off-by-one errors arise). Nothing is a silver bullet. Static types can make life easier by preventing some meaningless code, but they don’t ensure correct programs.