Optimal Virtual Employee Software Engineer interview questions

The interview process was medium and the interviewer was good and experienced one. I have faced 3 round of interview in which first was telephonic and second was f2f and third was hr. I have cleared all round but the company management was so bad and specially the Hr they don't have guts to take any serious decision. They even not hire you after offering you job they discussed salary and on the date of joining they call me and told me that i will inform you the date of joining. It was really worst experience i have ever faced. They wasted my whole day. One suggestion for management that stop playing with time of job seeker if you don't have requirement then why you are wasting time of others and you are at top management level so you should have guts to take decision with valid reason.