Automation is about timing, not volume
A behavioural flow outperforms a broadcast because it arrives on the day the person was thinking about the thing. A newsletter goes out on the second Tuesday because that is when the newsletter goes out. An abandoned cart email goes out four hours after somebody put something in a cart and did not check out. Same channel, completely different relevance.
Build in the order the money was already spent
Enquiry follow-up or abandoned cart first, because both act on demand you have already paid for. Welcome second, because it is the highest engagement window you will ever get with a new contact. Post-purchase third, as the cheapest route to a second order. Win-back fourth, for the people already lost. Campaigns last, because they need something worth saying.
Most programmes are built in the reverse order, starting with a newsletter, which is why so many of them never show a return.
How this page differs from email marketing
Automation is the email that sends itself: a sequence that fires because somebody did something, and keeps firing long after anyone last thought about it. Email marketing is the broader service and covers the things a person decides to send, the list strategy underneath, and the deliverability work that makes any of it arrive.
Build the flows first. They work the enquiries you already paid for, and they keep working while nobody is watching.