KISS:

Keep It Simple Stupid!

Axiom 1 (Murphy) All Programs are buggy

Theorem 1 (Law of Large Programs) Large programs are even buggier that their size would indicate

Corollary 1.1 A security relevant program has security bugs.

Theorem 2 If you do not run a program, it does not matter whether or not it is buggy.

Corollary 2.1 If you do not run a program, it does not matter if it has security holes.

Theorem 3 Exposed machines should run as few programs as possible; the ones that are run should be as small as possible