Why Deliverability Matters More Than Open Rates

The metric everyone's optimising for the wrong problem

Email marketing dashboards are full of open rates. Agencies report on them. Platforms benchmark against them. Marketers spend hours A/B testing subject lines to squeeze out another percentage point.

Here's the problem: your open rate only measures people who received your email. If half your list never sees the message because it landed in spam or was silently dropped by the mail server, that 40% open rate is actually 20% — and you'd have no idea.

Inbox placement is the real lever

Deliverability is the percentage of your emails that arrive in the primary inbox — not spam, not promotions, not the void. Every downstream metric (opens, clicks, conversions) depends entirely on this number.

The good news is that inbox placement is highly predictable once you understand what mail servers actually look at: sender reputation, authentication records (SPF, DKIM, DMARC), list hygiene, complaint rates, and engagement history. None of this is magic — it's just plumbing that most senders ignore until it's too late.

What damages your placement

The most common causes of deliverability problems are shared IP reputation (you're getting punished for someone else's spam), stale lists (sending to addresses that haven't engaged in 12+ months), and missing or misconfigured authentication records.

A single month of sending to a dirty list can take six months to recover from. Gmail's filtering algorithms are long-memoried and unforgiving.

A simple rule to live by

Before you optimise your subject line, check whether your last campaign hit the inbox. Use Google Postmaster Tools, monitor your bounce rate, and watch your complaint rate like a hawk. Keep it below 0.1%.

At PristineSend, we make this visible by default. Delivery status, bounce classification, and complaint rates are first-class data — not buried in a CSV export.