Packaging and/or Deploying. Sometimes you want to install the program you just compiled so that it can be run from anyhere on the system, and other programs or users can find it.Running basic tests on a project every time it’s built can be a good way to ensure that bugs get fixed and stay fixed. Also, it frequently happens that bugs, once fixed, creep back into code. Testing the build results. It’s essential to know when you’ve introduced bugs sooner rather than later new bugs are often easy to fix, and old bugs are often not so easy to fix.Keeping track of dozens of libraries, and references to those libraries by hundreds of source files, can be an ugly business.
A change to code in a single library can have effects across your entire project, and might require some or all of your code to be recompiled - and often in a particular order.