Why is my chance of theft discovery high even if a guard is nowhere near? [duplicate]

I've noticed the sneak mechanic in Kingdoms of Amalur: Reckoning is a fickle mistress. From what I can tell, if anyone saw you in the vicinity at any point, even when you sneak they'll still be aware of your presence.

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Even though I'm not in anyone's direct line of sight, they're still alert to my presence when sneaking. To remedy this, you can simply wait in that same spot for a short period of time. Their awareness will gradually decrease over time, resulting in:

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As that meter decreases, your chance of being caught while stealing will also decrease!