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Pre-deploy workflows will execute when a deploy request is submitted if the checkbox to run the pre-deploy is selected. The project should have the Pre-deploy workflow selected in the configuration screen. The workflow inputs for Pre-deploy should be setup to match the corresponding Deploy workflow of the project. The deploy workflow's inputs will show on the project deployment and release configuration screen. If they aren't also present in the Pre-deploy workflow, the data will not make it through to the deploy workflow. The Pre-deploy workflow inputs flow into the Deploy workflow inputs. For this to work, workflow developers must use the same name and data type for the Pre-deploy output(with "Return As Output" selected) and Deploy input variables in the respective workflows. To learn more about workflow inputs see Creating a Workflow.
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