kiss her already

Someone asked me "How do I know when to kiss her?" 

I laughed off the question, at first, and then actually thought about it. We don't ever really know when to kiss her. Or him. We only know when the risk of being rejected by the attempt is low enough that we're comfortable, or at least worth the risk. But isn't that the thrill?

When is getting the kiss not worth a thousand rejections?  

Like most things in life.