Why are static testing and dynamic testing described as complementary?

Q. Why are static testing and dynamic testing described as complementary?

Before we get to know why do static and dynamic testing described as complementary, we need to know about each technique of software testing.

Static Testing is a software testing technique in which the software is tested without executing the code.
The process provides an understanding of the code structure and can help to ensure that the code adheres to industry standards.

Dynamic Testing (or dynamic analysis) is a term used in software engineering to describe the testing of the dynamic behaviour of the code. That is, dynamic analysis refers to the examination of the physical response from the system to variables that are not constant and change with time.

In this process, the dynamic behaviour of the code is tested.

The aim of both the technique is to identify the defects.

Since static and dynamic testing is independently used to analyse a software program.

Both the testing does not have any direct competition with each other that is the reason static and dynamic testing described as complementary.

Static analysis is performed in a non-runtime environment. Typically a static analysis tool will inspect program code for all possible run-time behaviors and seek out coding flaws, back doors, and potentially malicious code.

Dynamic analys is adopts the opposite approach and is executed while a program is in operation.