I have a workflow on a picklist that only fires on create regardless of the Evaluation Criteria. I have changed the workflow multiple times to no avail. I have tried "Evaluate the rule when a record is created, and any time it's edited to subsequently meet criteria" and "created, and every time it's edited" yet it only fires when the record is created. I deleted the workflow and recreated it, but the same outcome persists. I am working on a developer org. Any thoughts?
If you want it to fire on every update, regardless if there were changes, then definitely use "When created and every time it's edited". If you use the "..and every time it's edited to subsequently meet criteria" it would have be updated at least twice: once to not satisfy the criteria and then back again.
Could there be another automatism "invalidating" the record?
Setup a Debug trace for your user with workflow level on at least info (should be default) and see what's happening in there. You should be able to see the criteria rule and values of the relevant fields.