When you start a SharePoint Online workflow that uses the Microsoft SharePoint 2010 Workflow platform type, you experience one of the following symptoms:
The workflow displays a “Please wait while your workflow is started” message for about one minute.
The workflow takes longer than expected to finish.
Depending on the point at which you interact with the workflow, such as a web browser or through Microsoft Outlook, the workflow takes about one minute to respond when you approve a task or do a similar action. Examples of common situations that may experience this issue include such out-of-the-box (OOB) workflows as the following:
To work around this issue, convert the workflow from the SharePoint 2010 Workflow platform type to the Microsoft SharePoint 2013 Workflow platform type.
Note This method requires you to rewrite the whole workflow. Before you use this method, review your current configuration to assess the requirements.
This problem occurs because the workflow has to be compiled before it can be processed. The workflow is cached after the compilation process runs. However, the problem may also occur on other servers. Additionally, cached workflows are cleared at least every night but can occur more frequently.
If a workflow has to complete compiling before it runs, you will encounter this delay. SharePoint 2010 workflows enable enterprises to reduce the number of unnecessary interactions between people as they run business processes. Workflows such as an approval workflow generally require human interaction because they aren't designed to immediately process an action. Therefore, you may experience the behavior that's described in the "PROBLEM" section if the workflow has to compile.