COFE App Senior Android Developer interview questions

The interview process went on for almost 2 months. They take one round and get back to you after 15 days. Finally all the rounds finished, ceo also had discussion. And then again 15 days later they told me that they can't offer the salary that I was expecting.(the number which we agreed on before starting the process) Why waste someone's time? There was lack of communication and clarity through out the process. Overall it was totally negative experience for me.