Discover interview questions

My first HR interview was on March 2020, After that HR told me that someone from the company will contact me and they will set 3 interviews, I really liked to join this company so After one week I followed up! The HR answered one month later that sorry we will contact you bla bla it took almost 4 month and finally in July they set 3 meetings in two days, No one attended these meetings! Never heard anything from HR, And just received an automatic email that I'm rejected! The most unprofessional way I have ever seen. I'm happy that I didn't waste more time on these unprofessional process which shows whats going inside their team.