Quality is delighting customers
The bugs undiscoverd in previous stage/cycles is called bugleakage/defect leakage for that stage /cycle.
For example :
If you completed system testing(ST) and certified as fully tested and send it for acceptance test(AT).In AT if client found the bugs which are not detected in system testing phase is the bugs leaked from the ST phase to AT or client may found the bugs after release while using the application .
can any more points to be added??
Somehow the definition is right:
But - for me - a defect which is found by Client is not called "defect Leakage" - it's called bug/ defect? :)
Defect Leakage is the ratio between the bugs you find during testing & the bugs that occur at the customer.