Using the No Data Result Path

Overview

If a Flow step requires input that is not provided, the Flow will stop running. For example, if a step requires input data from a user-completed Form and the user submits the form with no data in the required fields, the Flow will not continue. Adding a No Data Result path solves this problem by allowing a Flow to proceed, even when a Flow step requiring input does not receive it.
Add a No Data Result path in the Flow Designer by selecting the Show No Data as Path checkbox in the Properties panel under the Outcomes section.

Example

In this example, the Flow will capitalize text supplied through a Form. If the Form is submitted without text, the Flow will navigate down the No Data Result Path.

Begin in a Designer Folder. Select Create Flow in the bottom action panel, name the Flow and select 'Create'.

In the Flow Designer, add a Show Form step from the Favorites category in the Steps panel to create a new Form. This Form has a Label, a Text Box, and a Button. Save and close the Form Designer to navigate back to the Flow Designer. 

On the Done outcome path, add a Capitalize step from the Data > Text category in the Steps panel. 

With the Capitalize step selected, select the output from the Form in the Properties panel under Inputs.

If the Form is submitted without text, the Capitalize step will need to detect this and display a second Form. Under the Outcomes section, select the Show No Data as Path checkbox. This creates a No Data Result outcome path.

On the No Data Result outcome path, add a Show Form step that will display when the first Form is submitted without data. This Form is designed with a Label stating "No Data Given" and a Button to finish the Flow.

Connect the Capitalize step's Done outcome path to the End step and the No Data Form's outcome path. 

Debug

Select Debug to run this Flow in the debugger.

In the first run of the debugger, don't enter any data into the first Form. The Flow will continue to run, directed through the No Data Result path, the second Form displays. 

Run in the debugger again by selecting Create New Session. This time add text in the first Form and notice the Flow navigates down the done path to the End Step. On the Capitalize step's output, the input text is now capitalized.