Deliverability is the thing you are buying
Technology
The campaign editor is not what makes Mailchimp worth paying for. The sending reputation is, along with bounce and complaint handling, the unsubscribe machinery, and a consent record that holds up in the places the list is read. Running all of that yourself has one bad failure mode: quiet delivery to spam.
The boundary that matters is between marketing email and product email. Mailchimp is built for the first: audiences, segments, campaigns, consent. Password resets and receipts belong on a transactional sender instead, on a domain whose reputation is not tied to a newsletter.
How to keep an email list from becoming a liability
- You are billed for contacts, not for sends
Mailchimp prices marketing plans on the size of the audience, so a contact who has not opened anything in two years costs the same as a buyer. Nobody notices until the invoice does. Treat pruning and re-engagement as cost control on a schedule, not as an occasional cleanup project.
- One audience with tags, not many audiences
An audience is a separate list with its own subscribe state. Teams that spin up a new one per campaign end up with the same person stored twice, two consent records to honor, and reporting that will not join. Tags, groups and segments do that work inside a single audience.
- The wrong tool for transactional mail
Password resets, receipts and alerts have to land in seconds, on a sending domain that is not carrying a newsletter's complaint rate. Mailchimp is a campaign sender. Putting login email through it means one unsubscribe click can quietly cut somebody off from their own account.
Mailchimp has not yet appeared in a Monogram case study we have published. The marketing platform we have shipped against most is HubSpot, where the platform stays the system of record and the form stays in our own components. The same split applies here.
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