I close the ones I do not need and hence, I am left with consolidated results at the end. That is why I have put on the habit of using new tabs every time. During the process, did you ever lose track of where you started from? Did you also lose sight of an interesting result which you saw somewhere on the Google result page and decided to check it a bit later, only to come back and realize you can’t find it? This probably happened because you used the same browser window and tab for the entire session.
I am sure that you too must have done something similar at some point in your life. And whenever I am on to such a thing I navigate from one link to another, visit many websites and exhaust all Google options. A major part of my writing job involves performing extensive research on the internet.