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If there is a web application that holds important data, how important is it to use a complex/long/secure passphrase?
When I use for example something like "applefreezer" as password for my admin account in a forum, one would say that its not very secure. No special characters, not long enough, predictable words and combinations. And of course, I would never use this with an important encrypted piece of hardware.
But if I know, that a web application is programmed to prevent brute force attacks and even password lists, why should I need a passphrase that withstands these kind of attacks?
One reason might be, that someone could crack the password when he/she hacks data from my database. But honestly, if someone hacks the server, the password is senseless anyway. Of course, its important then that its not reused in other applications.
TL;DR do I need complex passwords for applications that prevent bruteforce/list attacks?