This doesn't work. Users learn to ignore the message.
Imagine I just entered a command to remove too many servers that will cause an outage:
"Finished removing servers"
(better than no message, I suppose)
vs "Finished removing 8 servers"
(better, it's still too late to prevent my mistake
but at least I can figure out the scale of my mistake)
vs "8 servers will be removed. Press `y` to continue"
(better, no indication of impact but if I'm paying
attention I might catch the mistake)
vs "40% capacity (8 servers) will be removed.
Load will increase by 66% on the remaining 12 servers.
This is above the safety threshold of a 20% increase.
You can override by entering `live dangerously`."
(preemptive safety check--imagine the text is also red so it stands out)