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