Three things made it defensible
Judge outbound on payback, not on ROI multiples
The pitch you'll get is a deal worth $21,120 in annual contract value against $9,060 of monthly spend. Sounds great. It isn't, if you bill monthly and the deal landed in month five.
My rule is one to one and a half times the first month's recurring revenue to acquire a customer, and I'll spend it happily when retention runs past twelve months. Different question, different answer.
Two campaigns is not two motions
The team was running two segments as two separate operations. When I ran the revenue analysis, 11 of the top 20 accounts sat in the same sub-segment. 55%. Same product, same buyer, mostly the same problem.
So: two campaigns with different content, one motion, one cost base. The other segment moved to organic and search, where it belonged.
Check the signal before you act on it
If you trigger calls off email opens, most of your triggers are firewalls. An open that fires in the same minute as the send isn't a person. Require a gap of at least three minutes, and spacing between subsequent opens.
Inbox privacy protection creates the same false positive across your whole list. Get this wrong and your SDR spends the week calling people who never read the email.