Hi @hhkim,
Configuration nodes are used, as the name suggests, to configure things. If they are at the top-level of a workflow, they represent configuration options of that workflow. If they are inside a component, they represent the component’s configuration options. If you used many different components in your workflow, would you like their configuration to show up in the Hub UI? Instead of doing that, you have two options:
Put configuration nodes at the top-level of your workflow and pass the flow variables inside your components. If the config node is at the top-level, it shows up in the Run or Deployment Configuration sidebar in the Hub UI.
Create a data app that uses widget nodes (e.g. String Widget) to ask for information from the user. See our beginners guide for more info on that.