Online dating rule: 3 and done You receive an online dating email from a cute guy. Congrats! Now, after three emails back and forth (you've sent three, he's sent three), it's time to either make plans to meet in person or move on, says Match.com relationship expert Whitney Casey. ' (Not getting as many replies as you'd like? Learn How to Write the Perfect Online Dating Message.) I picked her brain recently about her "three and done" online dating rule. Here's what I learned about the rule and how it can help me (and you!) find love in the digital age: Imaginary Lovers "Chemistry isn't found online; it's found in person," Casey says. Online dating is all about filling in the blanks. That's because online, daters have less information to go work with, and so they fixate on little "clues" to figure each other out. After exchanging loads of messages, you'll both have created entire personas for each other, which are probably quite a bit different from reality. "Great email does not a great relationship make," Casey says. Take it to table and see if you really click. And whatever you do, don't bring up one of the 5 Subjects to Avoid on a First Date. My two cents: I've been let down several times by not following this advice. On more than one occasion, I thought a guy was perfect from our messages, only to be sorely disappointed when we met in person. Still, I don't think I should go out with every guy I message three times. I need to be a little more selective about who I spend my time getting dolled up for. Investment Options A date takes just an hour. But dozens of emails back and forth? That takes weeks. Invest that much time before every one-hour date (most of which probably won't go anywhere) and you'll be worn out, discouraged and borderline bitter in no time, Casey says. My two cents: Checking and sending messages is really eating away at my schedule. More time and more dates? Sign me up! (Which site will land you the best dates? Learn How Dating Sites" Matching Systems Work.) Numbers Games Online dating is, in its essence, a numbers game. You have to kiss a lot of frogs before you can find your prince, right? And if you have all your time tied up in messaging frogs - and not kissing them - you're seriously hurting your chances of finding your prince. My two cents: Sounds tiring...but true. I'll start stocking my purse with mints! This content originally appeared as "Online Dating Rule: Three and Done" on Women's Health.