In this 10 minute video, you'll see how to use the Commit Pending Changes action in Nintex Workflow for SharePoint and Office 365.
SharePoint executes in batches of actions, so the order of actions that you set in your workflow may not be the same as the order that those actions are processed. If you have two actions that must happen in a specific order such as pasting a document into a folder, and then copying that document into a second folder. It's possible that the copy action may happen before the paste action is complete.
In this video you'll see how to use the commit action to force SharePoint to process you actions in the desired order.