It is incredibly obvious to people with the knowledge and skills. They can look at code and just by glancing at it can have a gut reaction that triggers red fl

It is incredibly obvious to people with the knowledge and skills. They can look at code and just by glancing at it can have a gut reaction that triggers red flags. Sometimes it can even be an emotional disgust. It's just not common knowledge. We as a community need to do a better job at transferring this knowledge. Proper strong typing, not just the weak typing that is more common, provides these "danger detectors". It makes it a compile error. Compiler errors make things immediately obvious. Type systems are very rich and most statically typed languages that are commonly used now can barely count as type systems when compared against what we know from mathematics and computer science. They merely describe the data format (or not in the case of nullable) and not acceptable inputs. They don't allow types for scenarios like requiring a function that exhibits these behaviors but not these other ones. Pattern matching in combination with strong typing requires code that handles all possible inputs or you get a compiler error. Dependent typing requires inputs to be within certain tolerances (not just adhering to a data format). Type systems can also make certain race conditions impossible to create.