Rain fade and link budgets
The link degrades gracefully until it does not. Reading the margin tells you which side of that you are on.
Writing
operations
Vendor defaults that will hurt you
Shipping defaults are chosen so the device works out of the box, not so it is safe.
Configuration backups that are actually restorable
A directory of config files is not a recovery plan. Here is the gap.
Junos commit and rollback: the feature worth envying
Configuration as a transaction changes how confidently you can work.
Three questions before touching a production network
Not process for its own sake. Three questions that have prevented more outages than any tool.