What you're describing is block coverage, which is only one of many types of code coverage that exist. By itself, it is rather limited in the types of issues i

What you're describing is block coverage, which is only one of many types of code coverage that exist. By itself, it is rather limited in the types of issues it can discover. There are many other types of code coverage, including branch/conditional coverage, state coverage and so forth that provide much greater depth of coverage that developers should look into using where possible. The Wikipedia article has a good introduction: https://en.wikipedia.org/wiki/Code_coverage https://en.wikipedia.org/wiki/Code_coverage.