> For the complete documentation index, see [llms.txt](https://magdalenaolak.gitbook.io/istqb-foundation-level/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://magdalenaolak.gitbook.io/istqb-foundation-level/1-fundamentals-of-testing/1.2-why-is-testing-necessary.md).

# 1.2. Why is Testing Necessary?

Rigorous testing of components and systems, and their associated documentation, can help reduce the risk of failures occurring during operation. When defects are detected, and subsequently fixed, this contributes to the quality of the components or systems. In addition, software testing may also be required to meet contractual or legal requirements or industry-specific standards.

{% content-ref url="/pages/-MRCMQQ0h5lTBQPuFWB1" %}
[1.2.1 Testing’s Contributions to Success](/istqb-foundation-level/1-fundamentals-of-testing/1.2-why-is-testing-necessary/1.2.1-testings-contributions-to-success.md)
{% endcontent-ref %}

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[1.2.2 Quality Assurance and Testing](/istqb-foundation-level/1-fundamentals-of-testing/1.2-why-is-testing-necessary/1.2.2-quality-assurance-and-testing.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MRCMv\_eTubukfo5Z8sa" %}
[1.2.3 Errors, Defects, and Failures](/istqb-foundation-level/1-fundamentals-of-testing/1.2-why-is-testing-necessary/1.2.3-errors-defects-and-failures.md)
{% endcontent-ref %}

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[1.2.4 Defects, Root Causes and Effects](/istqb-foundation-level/1-fundamentals-of-testing/1.2-why-is-testing-necessary/1.2.4-defects-root-causes-and-effects.md)
{% endcontent-ref %}