Tests that are designed to find bugs and
tests that are designed to cover critical business process are not
necessarily the same test. There are certainly potential for overlaps.
For example, it is common knowledge that the area where features
intersect has a higher percentage of producing bugs but not all of the
feature intersections are critical area.
If a team adopts the strategy of capturing tests from defects,
especially if the tests are to be automated - they need to be
selective. Because there is a cost in creating and maintaining an
automated tests. Unless the team has unlimited resource and time, they
need to be aware of where the defects are generated before automating
the tests. (Of course, critical defects from customers usually
indicative of a critical business process - but again not always).