Abnormal End
An abnormal end occurs when a component or system stops executing unexpectedly before completing its intended operation.
“The unintended termination of the execution of a component or system prior to completion.”
(Definition reproduced from the ISTQB Glossary. Copyright belongs to ISTQB.)
View the complete ISTQB GlossaryWhat is Abnormal End?
An abnormal end is an unintended termination caused by defects, unexpected input, resource failures, or environmental problems. Testers investigate the conditions that caused the system to stop unexpectedly.
Typical causes: Programming defects, invalid data, unavailable resources, and hardware or network failures.
How testers detect it: Testers execute scenarios that may trigger unexpected termination and verify that failures are handled gracefully.
Importance in testing: Detecting abnormal ends improves system reliability and prevents critical failures in production.
Visual Example
An abnormal end interrupts execution before the normal completion point.
1. Processing starts
A job, transaction, or service call begins normal execution.
2. Execution stops
The component terminates before the work reaches completion.
3. Tester checks recovery
Rollback, logs, alerts, duplicate prevention, and restart behavior are verified.
Real World Example
A healthcare platform sends medication orders from a prescribing module to a pharmacy service, and each order must either complete fully or leave a clear record that it did not.
During testing, the service is terminated just after the order is saved locally but before the pharmacy acknowledgement is received. Abnormal end is the right concept because the concern is unfinished execution, not simply an incorrect message on the screen.
The tester checks whether the transaction rolls back or resumes safely, whether audit logs show the interrupted step, whether duplicate medication orders are prevented, and whether clinical staff receive a clear status after restart.
Understanding Abnormal end helps the team protect patient safety because they test what happens when processing stops halfway through a critical workflow.
Practice Questions
Question 1
During a nightly claims payment batch, the process terminates after writing some payment records but before producing the completion report. Which term BEST describes the observed event?
Question 2
A tester wants to evaluate how a hospital medication service handles abnormal end. Which test is MOST directly relevant?
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