One of the sneakiest production issues in n8n: the workflow runs green, no errors, execution shows 
— and nothing actually happened.
I’ve debugged a dozen of these. Here’s the pattern breakdown and how to catch each one before it bites you in prod.
1. The “no items” branch that silently exits
You have an IF node that routes based on whether a value exists. If it doesn’t, the false branch just… ends. No error. No email. No Slack message. You find out three days later when someone asks “why didn’t the automation run?”
Fix: Every branch that “should never happen” should end with a Slack/email alert node or at least a Stop And Error node. Treat silent exits as bugs.
2. The HTTP Request that returns 200 but the API failed
Many APIs return 200 OK with {"success": false, "error": "Invalid token"} in the body. n8n doesn’t know this is a failure — it just passes the response downstream.
Fix: After any HTTP Request to an external API, add a Filter or IF node that checks {{ $json.success }} or whatever field the API uses. Route failures to an error handler.
3. The Set node that overwrites items you needed
You use a Set node to shape your data and accidentally toggle “Keep Only Set” — now all the original fields are gone. Downstream nodes get empty values, skip their logic, and complete successfully with nothing.
Fix: Be deliberate about “Keep Only Set.” When in doubt, leave it off and remove fields explicitly with a Code node or a second Set node.
4. The SplitInBatches loop that finishes early
You loop through 50 records, one errors on record #12 (say a malformed email address), and depending on your error handling settings the whole loop exits cleanly without processing records 13–50.
Fix: Use the “Continue On Fail” option on nodes inside loops. Capture errors in a separate branch (the error output of the node) and log them — then the loop keeps going.
5. The webhook that no one sent to
You built the whole automation. Tested it manually. Deployed it. But the source system was still pointing at the old webhook URL. Your n8n workflow is active and waiting — for a request that never arrives.
Fix: End-to-end test from the actual source system (not n8n’s “Test Workflow” button) before calling it done. Check your webhook node’s Production URL is registered where it needs to be.
Bonus: add a “heartbeat” to critical workflows
For any automation where silence = broken, add a scheduled sub-workflow that checks a timestamp in a database or Google Sheet:
Every 6 hours:
→ Check last_run_at in Airtable
→ If older than 12 hours → Slack alert "automation may be stalled"
It’s 10 minutes to build and has saved me from week-long outages.
What’s your most painful “succeeded but did nothing” story? Drop it below — I’m curious what patterns I’m missing.
If you’re tired of debugging these yourself, my team at Occelatus builds and maintains n8n workflows for founders and ops teams. Happy to answer questions here regardless.