I’ve heard that Coffee Meets Bagel and Hinge can be a little different - for those more serious about actually meeting someone who wants an actual relationship because of the ways they work. Have you tried either of those?
I have not tried those, so I will see how it goes!
I’ve been on both sides of the “ghosting.” If you met through a dating site, have not been dating long, and have not yet started an exclusive relationship; it is quite common. Interests can change over the course of the week, both due to learning more about each other and due to external circumstances beyond your control. There are countless possible reasons. Maybe she has been on dates with other people and wants to focus on other prospects. Maybe she was turned off by something, such as a long series of texts asking why she isn’t replying.
Whether it is worth the time and effort or not, depends on your priorities. Dating can be inexpensive, if you choose inexpensive activities. You don’t have to go to an expensive restaurant or bar, and offer to pay the bill. For example, I like to have first dates going on walks in a public and scenic area with my dog. It costs nothing but gas, is easy to talk/hear, is something I would have done on my own, is a good test for how well she’ll get along with my dog, and tends to have a high success rate compared to other activities. Once you attend grad school, I’d expect it will be far easier to meet people than with dating sites due to frequently spending time with a large number of single women, near your age.
Most I never met in person
Well, from a guy’s perspective, if I’d spent hours on the phone with someone, maybe days messaging with her, she told me she liked me, and I STILL hadn’t ASKED HER OUT, I wouldn’t be surprised if she ghosted me. The women here can correct me if I’m wrong, but I don’t believe they like to waste time on someone who they feel may be wasting theirs.
If you were interested in going out with them and had invested that much time and effort, why wouldn’t you ask them out? Ya gotta close the deal at some point, buddy. 
I did ask them out and we talked about meeting in person.
Talking about meeting in person is not the same as asking them out, and you can’t wait forever. Asking them out means you ask and IF they say yes, you propose a definitive date and time or ask when they’re available and set it up. If they don’t want to do that, then that’s a sign they are not really interested. If you don’t ask after spending all those hours on the phone and messaging, they’ll wonder if you’re playing games, and rather than confront you on it, they’ll probably just stop communicating.
In my opinion. 
I did ask them out and we talked about meeting in person. Other times it was actually the other way around and they asked me out and we talked about meeting in person. We had a prospective time in mind (either that weekend or a day during the week).
Like I said before, my only guess is some girls talk with multiple guys and then chooses.
I don’t think you’re following me, so I’ll try one last time here and then I give up. Did you set up a specific date? Saturday at 7:00 at X restaurant, for example? If you did and they didn’t show up and ghosted you, then yes, that’s rude. If not, you didn’t ask them out. You just talked about meeting in person at some point during the week or weekend to be determined later - after you’ve already spent hours talking to them and messaging with them, perhaps over multiple days. What are you waiting for?
If some of them asked YOU out, you set it up right then - assuming you actually wanted to go out with them. If you don’t and just keep calling and messaging without proposing and confirming an actual date, time and place for the date, at some point they’re going to cut it off.
The date was set. They stopped communication about the date was set.
I know how to ask out a girl because I have been on many dates throughout my life.
Also, if you are the person getting asked out, you should let the person that asked you out make the plans.
MODERATOR’S NOTE:
There seems to be nothing original to add, and since the discussion is circular, I’m closing.