How Software Checks User Input

​The software performs a user input check to see if you have chosen all your settings before starting a new operation. This is once again critical because if the software does not check all your inputs, the data obtained in the output could be false or otherwise it may not perform any operation at all. 

Example

As you can see the software is ​not starting and showing an Error Pop-up Message to choose all your settings before you can proceed further.