Security In Terms Of Delay

Consider the following:

• Time lock safes
• Passwords can be brute-forced, their strength is measured in time needed to brute-force
• When you lose your key, you call a locksmith
• Repeatedly entering the wrong password on some systems forces you to wait before you can try again
• High security areas need to be checked regularly

I'm just thinking, we can express how secure something is by how much time it takes to break in. Adding security can be thought of as delaying break ins. Interval between security checks needs to be less than the time needed to break in.