Two "Define Query Params" why?

I am creating a new site that uses URL parameters to filter different bits of data from my database.

Step 1: App Structure - Add an App ID and click Define Query Params to create a variable called “id”
Step 2: Server Connect - Add a $_GET variable called “urlfilter”, open the query conditions and assign $_GET variable, save
Step 3: App Structure - Server Connect data component added, input parameter of “urlfilter” assigned to “query.id”

I would imagine this should be all that was needed, but it did not work as expected, I had to add a Query Manager, added id “query_id” and defined the same “query.id” variable created in Step 1

Are there meant to be 2 places where i need to click the Define Query Params like this, and if so, why?
Is one for server side and the other for client side or something.