What does the "Health Monitoring" requirement... lab environment?

What does the “Health Monitoring” requirement mean when setting up a penetration test lab environment?

The tester needs to be sure that a lack of resources is not the cause of false results.
The tester needs to be able to determine the causes when something crashes.
The tester needs to ensure controlled access to and from the lab environment and restricted access to the internet.
The tester validates a finding running the same test with a different tool to see if the results are the same.

Explanation & Hints:

Some requirements for a typical penetration testing environment are:

Closed network: the tester needs to ensure controlled access to and from the lab environment and restricted access to the Internet
Health monitoring: when something crashes, the tester needs to be able to determine why it happened
Sufficient hardware resources: the tester needs to be sure that a lack of resources is not the cause of false results
Duplicate tools: a way to validate a finding is to run the same test with a different tool to see if the results are the same