ISTQB-CTFL Questions Bank

The question is about marking the correct sentences among the given statements related to defects, failures, and mistakes. According to the ISTQB glossary, the definitions of these terms are1:

Defect: A flaw in a component or system that can cause the component or system to fail to perform its required function, e.g. an incorrect statement or data definition. A defect, if encountered during execution, may cause a failure of the component or system.

Failure: An event in which a component or system does not perform a required function within specified limits.

Mistake: A human action that produces an incorrect result.

Therefore, out of the five given statements, only two are correct, namely:

A human mistake may produce a defect: This is true, as a mistake is a source or cause of a defect, e.g. a programmer may make a mistake in writing a code statement, which results in a defect in the software component.

When a defect exists in a system it may result in a failure: This is true, as a defect is a potential or actual cause of a failure, e.g. a defect in the software component may cause the system to fail to perform a required function when the defect is encountered during execution.

The other three statements are incorrect, namely:

Defects are a result of environmental conditions and are also referred to as “Failures”: This is false, as defects are not a result of environmental conditions, but of mistakes or other factors, and defects are not the same as failures, but rather the causes of failures.

A system will totally fail to operate correctly when a failure exists in it: This is false, as a system may not necessarily fail completely or stop operating when a failure occurs, but may continue to operate with reduced functionality or performance, or with incorrect results.

Defects occur only as a result of technology changes: This is false, as defects can occur due to various reasons, not only technology changes, such as human mistakes, design flaws, requirement changes, hardware failures, etc.

References:

1: ISTQB Glossary of Testing Terms 4.0, 2023, available at ISTQB) and ASTQB).

Test automation allows you to produce tests that are less subject to human errors, as they can execute predefined test scripts or test cases with consistent inputs, outputs, and expected results. Test automation can also reduce the manual effort and time required to execute repetitive or tedious tests, such as regression tests, performance tests, or data-driven tests. Test automation does not demonstrate the absence of defects, as it can only verify the expected behavior of the system under test, not the unexpected or unknown behavior. Test automation does not avoid performing exploratory testing, as exploratory testing is a valuable technique to discover new information, risks, or defects that are not covered by automated tests. Test automation does not increase test process efficiency by facilitating management of defects, as defect management is a separate activity that involves reporting, tracking, analyzing, and resolving defects, which may or may not be related to automated tests. References: ISTQB Certified Tester Foundation Level (CTFL) v4.0 sources and documents:

ISTQB® Certified Tester Foundation Level Syllabus v4.0, Chapter 3.3.1, Test Automation1

ISTQB® Glossary of Testing Terms v4.0, Test Automation2

Exploratory testing involves simultaneous test design and execution and is guided by a test charter, which outlines what needs to be tested, how it should be tested, and what to look for. This technique is typically conducted within predefined time periods, known as time-boxing, which allows testers to explore a system, understand its functionalities, and identify potential issues without detailed documentation or prior test case planning. The key aspects of exploratory testing include flexibility, adaptability, and the ability to respond to system behavior during testing.References:

ISTQB Certified Tester Foundation Level Syllabus v4.0, Section 4.4.2.

The Waterfall model exemplifies a software development model that does not support the principle of early testing. In the Waterfall model, each phase must be completed before the next begins, which delays testing until after the completion of the earlier phases like requirements gathering and design. This can often result in finding defects later in the development cycle, making them more expensive and time-consuming to fix​ (ISTQB not-for-profit association)​​ (ISTQB not-for-profit association)​.References:

ISTQB® Certified Tester Foundation Level Syllabus v4.0:

ISTQB News Release on CTFL v4.0: