Why are programming libraries commonly used in software development?

Programming libraries are commonly used in software development primarily because they foster code reusability and efficiency. Libraries contain pre-written code that developers can use to perform common tasks or functions, which allows them to avoid writing code from scratch for every feature or functionality. This reuse of code not only speeds up the development process but also enhances consistency and reduces errors since the libraries are often well-tested.

When developers utilize libraries, they are able to focus on unique aspects of their application rather than reinventing the wheel for standard operations. This leads to less duplication of effort and can significantly decrease the time and resources needed to develop software. Additionally, using libraries can make it easier for teams to collaborate, as they can leverage shared resources that everyone understands.

In contrast, other options do not accurately capture the primary benefit of using programming libraries. For instance, while they may help with debugging to some extent, this is not their central purpose. The assertion that they increase application startup time is typically false because utilizing libraries often helps with optimized performance. Lastly, while libraries can provide some level of documentation through their usage examples and API references, they do not inherently reduce the need for documentation; in fact, good documentation remains essential to understand how to effectively use those libraries.