That doesn't make sense, for all you know a target is going to be reimaged in the next thirty seconds - the lower bound is always infinitesimal. There's a possibility you will have to compromise again if you are detected or ejected before your goal is achieved... so what?
As I've already said, disagree. I don't think there is any realistic scenario where the value changes, and therefore nobody should be focussed on persistence. It's a buzzword, and you've caught the buzz 
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