Why do interviews fail?

Question

Career in IT

I sent resumes to the VK/Telegram groups for the position of frontend jun.
Sometimes they write, they appoint an online conversation (they appoint somewhere after 5 days from the moment of the conversation, which seems to me a lot for a regular interview, but I don’t have much experience, so I don’t know). But the bottom line is that they were appointed conditionally on Friday, and from them on this day there is not a word or a spirit. And unfortunately it's not the first time.
What to do in such situations? Write to them in a personal? How often do such situations occur?

Answer 1

I have never had this, however, I was always called for face-to-face interviews.
Oh sorry, I missed it:
This is fine.
That is, it’s not normal, but don’t worry, look for a job further, send out your resume.

Answer 2

I sent resumes to the VK/Telegram groups for the position of frontend jun.

• Search for jobs through hh or MyCircle .
  
• Go to interviews in person, not online.
  

Answer 3

If they appointed on Friday and did not contact on Friday, then this is a typical galley, run and rejoice.