I think what you're saying is both besides the point and incorrect.
Firstly, not studying, ignoring safety rules, or half-assing a task at work are behaviors, they don't necessarily reflect understanding or intelligence. Sometimes I get up late and have to rush in the morning, that doesn't mean I lack the intelligence to understand that time passes when I sleep.
Secondly, I don't think that most people fail to see the connection between not studying and failing a test. They might give other excuses for emotional or practical reasons, but I think you'll have a hard time finding anyone who genuinely claims that studying doesn't usually lead to better test scores. Same for ignoring safety rules or half-assing work.