No, it's more because when the bug was filed, you said to yourself, "oh, was I supposed to update the $HOOZIWIZIT in that transaction, too? Oops." Code coverage

No, it's more because when the bug was filed, you said to yourself, "oh, was I supposed to update the $HOOZIWIZIT in that transaction, too? Oops." Code coverage won't save you from that. Matching test cases to requirements, or summat, can be helpful, but good golly it's a bunch more paperwork. Your point is a good one, but not where I was going.