Level 2^n: uses string concatenation in his SQL, for web forms passes plaintext passwords around in Javascript, has already been rooted and doesn't know it.
Level n^2: uses stored procedures, knows that cross site scripting and sql injection is bad, stores passwords in a form other than plain text, may block certain kinds of 'naughty' inputs (e.g. http://xkcd.com/327/ )
Level n: uses whitelists to validate input, does not use windows or SQL Server for anything, understands that security has a price (eternal vigilance) can explain what salting and hashing are, can protect your password against malicious database admin.
Level log(n): can protect against social engineering, audits OpenBSD for jollies, has transcended the need for users to create accounts and enter passwords, is completely unable to communicate with outside world since all their email has been PGP encrypted since the late 90s.