What’s “temporal engagement decay”?

Temporal engagement decay describes the pattern where email engagement is highest immediately after a trigger event and decreases as time passes:

The pattern:

A welcome email sent immediately after signup gets higher engagement than one sent a day later. Cart abandonment emails sent within an hour recover more carts than those sent after a week. Interest and intent fade over time.

Why it happens:

The trigger event represents peak interest or attention. Memory fades. Competitors may capture the opportunity. Life circumstances change. The moment passes.

Implications for automation:

Speed matters for many triggers. The first message in a sequence typically performs best. Subsequent messages face compounding decay. Long sequences may see diminishing returns.

Exceptions:

Some sequences build engagement over time through relationship development. Re-engagement may take multiple touches to succeed.

Strike while the iron is hot. The closer to the trigger, the more responsive the recipient, for most automation types.