I think in a LDR you're not seeing the person in different situations, like what they're like around your family, in the morning and the evening if that makes sense?
Someone could fake themselves face to face as well though? What are your thoughts? I think it's possible for someone to fake themselves face to face as well though.
A relationship is spending time together, seeing each other...getting to know each other in PERSON..not on the phone, text or email. I would NEVER do the long distance thing again. As someone mentioned earlier..there needs to be a lot of commitment on both sides and there has to be an end date.
I can't afford to travel all the time and only have so much time I can take off, so in my situation a long distance relationship is not convenient. And someone mentioned 'open relationship'..well, to me..why bother? That's another thing...I really love the physical part of the relationship, not only the sex...but cuddling, hugs...and when the major form of communication is skype or telephone...where is the touching?
There's a lot that gets missed on Skype (if you do Skype), and 1 or 2 hours a day of "I'm happy/you're happy" talk is not real life. Only when people live in the vicinity does real life set in, and then you can tell if you're suited to one another. Which is not to say there aren't people who have decided to have a go at a relationship that started long distance. There are, but you have to be very open-minded and patient once you finally are in real time with the person, because you're going to find out things you didn't on the all-sweet-all-the-time talk on Skype and e-mail.
Sure you can develop feelings based on talking and emailing. But you have to allow for the fact that your pen pal is a still complete stranger. There is no way to predict chemistry, or how you will feel upon meeting. Did you ever meet someone that was 'on paper' perfect for you, yet there was just something you could not vocalize that felt wrong? How do you judge their social interactions, familial relationships, work ethic or even their smell when you just chat online? There are just too many unknowns for your feelings to be real.
This is my take on it.