Which one of the following statements about system testing is NOT true?
-
System tests are often performed by independent teams.
-
Functional testing is used more than structural testing.
-
Faults found during system tests can be very expensive to fix.
-
End-users should be involved in system tests.
System testing is typically performed by independent test teams (A is true). Functional (black-box) testing is indeed used more than structural (white-box) testing in system testing (B is true). Faults found during system testing are very expensive to fix because they're found late (C is true). However, end-users are typically involved in acceptance testing, not system testing - system testing is conducted by the test team against specifications, making D the statement that is NOT true.
The correct answer is that end-users should be involved in system tests — as stated, this is NOT generally true and is the odd one out. System testing is typically performed by an independent test team against the whole integrated system before release; direct end-user involvement is characteristic of acceptance testing, a separate later stage. The other three statements are standard, accepted facts about system testing: independent teams often run it (avoids developer bias), functional (black-box) testing dominates over structural (white-box) testing at the system level since internals of the whole system are hard to instrument, and faults discovered this late are expensive to fix because they may require redesign across components. So the statement singling out end-user involvement is the false/NOT-true one among the four.