The most typical scenario for utilising parameters in filters is when you have many data sources that are not connected but have a common field. When there is only one data source, parameters are of limited use since basic filters function better.
When you need common filters across numerous sources, but can't combine them into a single source because you don't want to lose part of the functionality in each sheet, parameters come in handy.
If you have many data sources with varying degrees of detail but all of them have the same filterable field, such as user id, you may define a parameter based on that field (and recent versions of Tableau can automatically update the content of the parameter on loading the workbook). To filter across the sources, add a parameter called user id parameter that is updated when the workbook is opened, and then filter each individual page using a calculation like [user id]=user id parameter, where the user id comes from the applicable data source in each case. When the parameter is modified, each distinct data source will be filtered to reveal just the data associated with that user id, even if the data sources are otherwise unrelated.
This capability greatly simplifies the process of developing "universal" filters that operate across many data sources in a worksheet (now that parameters may change on load).
If you just have one data source, the strategy still works, but it's no better than simply filtering on the appropriate field (and don't forget, you can apply a filter to all sheets or a range of sheets).