Why it's good to "Err on the side of Caution"

As chatted with my friend this afternoon:

   me:  so there's 3-4 people walking around the aisles near me, one's an attractive young 30-something blonde so i do my thing, get my print-outs, fill up my water bottle - pretty much everything/anything I can do for a glimpse at her  and i'm sitting at my cube (which is at the end of the aisle and rather open to everyone who walks by) eating my  apple and echolocating every step of her heels and she finally passes by so I glance up, and she catches me off guard with "How's the apple?" all friendly like so contrary to all my hopes of contact with her, I impulsively react with a feeling of "do I know you" and all I could sputter out was "It's good." like a lametard and then I realize a second  later I could've been a bit more jovial about it, but it's better I erred on the side of caution otherwise I might blurt something really stupid out like, "I'd rather take a bite out of YOU " haha
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