Online dating causes some issues. You hold the other person in a certain view. When you meet them that view might change causing some problems. Yes, you believe the same things and think of them as well but they have some habits you could never ignore. Leaving the seat up, snoring, leaving dirty dishes in the sink, being a slob, or they could be obsessed with cleaning with a slight OCD.
Also, no one talks online like they do in real life. They might sound simple, intelligent, and thoughtful online. However, this might not be true. For example, people have told me I sound calm and patient online. Trust me, this is false.
If you do attempt online dating, please use video chat before you decide to meet with them.