How can sending velocity affect reputation?

Sending velocity refers to how quickly you send emails. High velocity is a strong spam indicator.

Why velocity matters:

Humans can only type and send so fast

Automated systems can send thousands per minute

High velocity strongly correlates with bulk operations

Receiving servers impose rate limits based on velocity

Velocity thresholds:

Individual mailbox accounts have technical limits (varies by provider)

Beyond limits, messages are deferred or rejected

Even within limits, high velocity raises suspicion

Reputation effects:

Velocity contributes to sender profiling

Combined with low engagement, high velocity accelerates damage

Rate limit errors themselves can affect standing

Optimal approach:

Spread daily volume across business hours

Add delays between individual sends

Never send at maximum technical capacity

Match velocity to what genuine communication looks like

Practical implementation:

Configure 1 to 5 minute gaps between sends

Use 8 to 10 hour sending windows

Respect provider-specific rate limits

Throttle more aggressively for new domains