Run your tests every day
Don't tolerate failure - ALL TESTS MUST PASS
as soon as you let one failure through without fixing it:
you lose confidence in the tests (!)
when you don't have confidence in the tests, you stop running the tests every day
when you stop running the tests every day, more tests will start failing
A lose-lose situation: you went through the trouble of making your tests, but now you don't reap the benefits
