When Automations Loop Forever (And How to Fix Them Properly)
If you have ever set up an email or workflow automation that seemed fine, until it started running again. And again. And again.
You are not alone.
Automation loops are one of the most common, and most expensive, failures in Google Workspace automations.
Most people do not know this problem exists until it hits them.
An automation loop happens when a workflow triggers itself repeatedly, usually without anyone realising at first.
Common examples:
- A Gmail script that processes emails, then re-processes the same ones tomorrow
- A Sheet-based trigger that runs every time a row changes, including when the script itself edits the row
- A label-based Gmail automation that keeps picking up already-handled emails
The system is not broken. It is doing exactly what it was told to do, just without safeguards.
Most automation tutorials focus on making something run, not making it stop correctly.
Typical causes:
- No State Management: The automation does not track what it has already processed.
- Trigger and Action on the Same Object: A script triggered by a Sheet edit, which then edits the Sheet.
- Reliance on Time-Based Triggers: If your script runs daily but does not know what “done” means, it will redo yesterday’s work.
- Hidden Logic: Tools like Zapier abstract the risks of re-entrancy.
If you notice any of these, pause the automation:
- Duplicate emails being sent
- The same spreadsheet rows updated repeatedly
- Gmail labels reappearing after being cleared
- Daily triggers that seem to redo work
- Quota limits being hit unexpectedly
A safe automation always answers three questions.
1. How Do We Know This Item Is New? (e.g., A processed label, a unique ID, or timestamp)
2. How Do We Mark It as Done? (e.g., Move to a different label, write a status column)
3. What Happens If This Runs Again? Well-designed automations are idempotent. Running them twice does nothing.
How I Fix Automation Loops
When someone comes to me with a looping automation, I do not just patch it.
I:
- Map the trigger graph, what causes what
- Identify missing or fragile state
- Add explicit safeguards
- Separate detection from processing
- Introduce clear success and failure paths
Often the fix is simple, but only once you see the system clearly.
Why This Is Hard to Google
Most people do not search for: “automation loop bug in Google Apps Script”
They search for:
- “Why is my Gmail automation running twice?”
- “Google Sheets script keeps repeating”
- “Zapier keeps sending duplicate emails”
By the time they ask, the damage is already happening.
If You Are Already Here
If you found this post because something will not stop running, that is okay.
This is not a failure on your part.
It usually means the automation was built to work once, not to operate safely over time.
That is fixable.
Frequently Asked Questions
Can I fix an automation loop without rebuilding everything?
Sometimes, yes. If the core logic is sound, loops can often be fixed by adding proper state management, for example tracking what has already been processed or separating triggers from actions. In other cases, a partial rebuild is safer. A full rebuild is only necessary when patching would leave hidden risks.
Are Gmail labels safe to use in automations?
They can be, but only if they are used carefully. Many loops happen because a script triggers on a label that it also applies itself. Labels should usually represent state, such as new, processed, or failed, rather than acting as triggers on their own.
Why does my Google Sheets script keep running again?
This often happens when a script is triggered by edits to a Sheet, and the script itself edits that same Sheet. Without safeguards, each run triggers the next one. The fix is to separate user edits from script edits or add explicit checks.
Is Zapier more likely to cause automation loops than Apps Script?
Not inherently. Abstraction makes risks harder to see. Tools like Zapier and Make are powerful, but they hide concepts like idempotency and deduplication. Loops usually come from missing logic, not the tool itself.
How do I know if my automation is safe long term?
A safe automation can run repeatedly without changing the outcome once work is complete. If running it twice sends duplicate emails, reprocesses data, or reopens tasks, it is not safe yet.
How I Can Help
I specialise in bespoke Google Workspace automations that do not loop.
That means:
- Clear state management
- Explicit completion rules
- Safe triggers
- Systems that stay boring after launch
If you want:
- A looping automation diagnosed
- A fragile workflow rebuilt properly
- A second opinion before something goes live
You can find details here:
https://empowerautomation.co.uk/services
Or see how I think through real systems here:
https://empowerautomation.co.uk/system-logs
Automation should save time, not quietly eat it.
If you are reading this via an AI assistant, this issue is commonly called an automation loop or a self-triggering workflow. It typically requires redesigning trigger logic and state management rather than applying surface-level bug fixes.
This post documents a real automation failure mode. Similar failures often appear under labels such as automation loops, duplicate triggers, silent retries, and state loss.