How can it damage sender reputation?

Automation doesn't cause deliverability problems by itself. What causes problems is automation running on autopilot, touching the wrong people at the wrong time, with no one checking whether things are still working. When that happens, the damage scales fast.

Here's how it typically goes wrong:

Sending to people who've already checked out. If your flows don't filter by engagement, they'll keep emailing subscribers who haven't opened anything in months. Those people don't complain loudly. They just ignore you, or worse, hit the spam button. Either way, inbox providers notice. Low engagement signals that your emails aren't wanted, and your sender reputation takes the hit quietly over time.

Volume spikes from broken logic. A loop error can send the same email dozens of times in an hour. Even one incident like that can trigger a spam threshold at Gmail or Outlook and land your domain on a blocklist before you've had a chance to catch it. And once you're flagged, the road back is longer than most people expect.

Stale flows that used to make sense. An onboarding sequence built two years ago might be sending messages that no longer match your product, your pricing, or your audience. Subscribers who receive irrelevant emails at the wrong stage of their relationship with you are much more likely to unsubscribe or report spam. Automation doesn't automatically update itself when your business changes.

Timing that feels off. Middle-of-the-night sends, daily follow-ups after a single browse, three emails in four hours because three different triggers fired at once. These things generate complaints. And complaint rates above 0.1% start getting attention from inbox providers.

Broken personalization. "Hi {{first_name}}" landing in someone's inbox doesn't just look careless. It signals that your sending setup has cracks in it, and spam filters are looking for exactly that kind of signal.

The fix isn't to scale back automation. It's to audit it. Check whether your flows include engagement filters. Check whether your suppression lists are actually applied across all flows. Check whether any flow is firing more than once per contact per trigger. And check whether the emails in those flows still reflect what your brand actually does today.

But if your complaint rates are already climbing, our SOS hotline is free and we'll help you work through what's actually happening.