Admins on Business and Enterprise accounts can delete custom workflows. In Enterprise accounts this is a controlled admin permission, so some admins may not have it.
Delete workflows you no longer use to keep your workspace neat.
Click your profile image in the upper right-hand corner of your workspace.
Select Settings from the drop-down.
Click Workflow in the left panel.
Right-click a workflow’s title in the list and select Delete workflow.
Click Delete to confirm your decision.
Open a workflow from your workflow settings page.
Use the three-dot menu in the top right-hand corner.
Click Delete and confirm in the pop-up that appears.
When you delete a custom workflow, if a task or project is currently in a status from the deleted workflow, then it remains in that status. However, you can't apply statuses from deleted workflows to additional tasks or filter by statuses that belong to deleted workflows.