Run a cold email infrastructure audit across DNS, mailboxes, warmup, and monitoring before you write a single subject line.
Retire a burned domain when the recovery math stops working. The signals, the cost comparison, and the decision framework that ends the debate.
Dedicated IPs help past 100k-150k emails a month sent consistently. Below that, shared IPs outperform. Here is the math.
The real math on cold email sending domains: mailboxes per domain, daily caps, and the point where more domains stop helping.
The metrics a cold email or sending vendor should guarantee in writing, with sample SLA language and red flags to reject.
