However some poeple run these "code quality" measures as part of a regular test suite, so if you write a method that has more than 3 lines you get a warning or failure.

In my opinion this leads to less readable code, as methods are prematurely refactored simply for size, and coders tend to do things like putting a hash literal on a single long line rather than formatting it for maximum readability.

This is just my opinion... I don't hold it against someone to use them, I just think they can make code less readable, not more.