I will not include a self-destruct mechanism unless absolutely necessary. If it is necessary, it will not be a large red button labelled "Danger: Do Not Push". The big red button marked "Do Not Push" will instead trigger a spray of bullets on anyone stupid enough to disregard it. Similarly, the ON/OFF switch will not clearly be labelled as such.
Pretty self-explanatory. Don't include it if you can help it, and if you absolutely must have one, don't make it obvious what it is.
And probably make it a code that someone can't randomly just guess.
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