"Many years later we asked our customers whether they wished us to provide an option to switch off these checks in the interests of efficiency on production runs. Unanimously, they urged us not to--they already knew how frequently subscript errors occur on production runs where failure to detect them could be disastrous. I note with fear and horror that even in 1980, language designers and users have not learned this lesson. In any respectable branch of engineering, failure to observe such elementary precautions would have long been against the law."

Humans are not good at programming. I've never seen a "done" C++ codebase in my life, maintainers are always too busy reinventing parts that had originally nothing to do with the feature scope of their library.