I wanted to create an example situation where you might want to create multiple content types to capture similar data. For this example, picture having a list which is meant to capture HR Questions. Typical HR questions could be along the lines of Benefits, Payroll, & Staffing. We could create an all-encompassing form and use it to capture the data however; this will plague our items with null (blank) values.
To not have all the blanks and to better target our users we could create a content type for each question type. Each content type ties back to the overarching idea which is “HR Questions,” but each content type drills down into more detail the components which comprise HR Questions. By doing this we can easily tailor each content type to only capture data relevant to that question type, but still have all the data stored in one list to easily create metrics.
Creating a central location for your users to Ask HR questions, gives you a central repository for the information, and will enable you to easily create metrics which encompass all of your results.