What is the "goal" of the PhD? I am little confused about the goal of PhD in the middle of my PhD. I used to think that PhD is equal to Research but in the middle of my PhD I find out that it is much more than only research. It involves TA work plus some other academic work and research also. Before joining the PhD my goal was to publish something revolutionary during my PhD but I believe that PhD is a process in which you do three things ( according to my seniors )


Work on some problem you find interesting 
Write and submit to some conference
If rejected again submit after modification


This is a typical PhD process. The above three steps will help me to get me a PhD, but it does not let me make a significant contribution which will help in finding job after PhD (postdoc, etc.). 

Question:  What is the "goal" of the PhD? Is it more than the above three mentioned steps? How to ensure that at the end of PhD I will have something significant research contribution? Do I only need to worry about this or my research supervisor also?
A PhD is about research. Of course, there are some other things - for example, in some universities you have to take classes because it is assumed that they help you with your research. TA is - in the universities I know - necessary to get money. Some supervisors also see their PhD students as their assistants and assume they help them with things not related to the research (e. g. with teaching, without compensating the student).

The goal of a PhD is to write and defend a PhD thesis. If everything is done correctly, this implies that the PhD student has substantial knowledge about her subfield and has made a groundbreaking contribution (but the ground that she breaks may be small!) Moreover, the student should learn in her PhD to be a professional researcher. This includes things like publishing, going to conferences etc. Those are then the things a PhD graduate will be evaluated on if she applies for academic jobs.

Your supervisor should, of course, also help you to become a successful researcher. However, it she does not care about you, the only thing you can probably do is to change your supervisor. However, you being successful is also good for her career.