Prevent workflow from starting new workflow instance of current workflow
Remove the workflow action "Start a Workflow" of the current workflow.
We had a user create a workflow "Workflow A" and the first step in the workflow was "start Workflow A". There needs to be a filter/configuration that prevents this as an option because became an endless recursive workflow instance. We removed the workflow, deleted the workflow, delete the item and then the list and this workflow still kept going. We then stopped the timer job and restarted IIS and this was still occurring. The ultimate fix was lock access to the site collection containing the item that the workflow was ran on.
To prevent this from becoming an issue for us or anyone else in the future a mechanism that would remove current workflow as an option would save much head headache. Yes, they could still create this same logic with 2 workflows, but the likelihood is far less.