LESSON 2 OF 6
Trigger, filter, action
BY THE END OF THIS LESSON
Describe any automation in the three parts every platform shares.
Three parts, whatever the tool is called
- Triggera form submitted, an email arriving
- Filtershould this one continue?
- Actionwhat happens
Every automation is the same shape. A trigger is the thing that starts it: a form submitted, an email arriving, a row added, a time of day. A filter decides whether this particular one should continue. An action is what happens.
Zapier, Make and n8n arrange these differently on screen and give them different names, but if you can describe your task in those three parts you can build it in any of them.
The filter is the part people skip
A trigger fires more often than you expect. Every email includes the newsletters, the automated receipts, and the reply you sent yourself two minutes ago.
Without a filter you have built something that runs constantly on things it should ignore — which is both the largest cost and the most common way an automation becomes noise nobody trusts.
Write it as a sentence first
Before opening any tool, write one sentence: when this happens, if these conditions hold, do this.
If the sentence needs an "and also" in the middle, that is usually two automations rather than one. Splitting them is almost always right — two simple ones are easier to fix than one that does everything, and when a step fails you know which job stopped.
WORKED EXAMPLE
NO FILTER
When an email arrives in the shared inbox, summarise it and post it to the team channel.
FILTERED
When an email arrives in the shared inbox, if it is not from one of our own addresses, is not an automated receipt, and the subject does not start with "Re:", summarise it and post it to the team channel.
The first version posts every receipt, newsletter and internal reply, and within a week the channel is muted — at which point the automation is worse than nothing, because the useful messages are in there too.
YOUR TURN
Write your automation as one sentence, filter included.
RUN THIS
I want to automate this: [describe it]. Write it as a single sentence in the form "when X, if Y, do Z". Then tell me what will trigger it that I have not thought of — the automated messages, the duplicates, my own replies — and what the filter needs to exclude. If it needs an "and also", tell me where to split it into two.
What a good result looks like
The list of things you had not thought of should be uncomfortably long. That list is the filter. If it comes back short, name your trigger more precisely.
KNOWLEDGE CHECK
Answer all 2 correctly to complete this lesson.
1. Why is the filter the part people most often skip?
2. Your one-sentence description needs an "and also" in the middle. What does that suggest?
REMEMBER THIS
When X, if Y, do Z — and the "if" is the part that decides whether anyone trusts it.