Many physicists claim that quantum mechanics may ultimately be able to explain all fundamental phenomena, and that, ttherefore, physical theory will soon be complete  However, every theory in the history of physics that was thought to be final eventually had to be rejected for failure to explain some new observation
For this reason, we can expect that quantum mechanics will not be the final theory
Your sister is a very good chess player but she has never won a chess tournament; ttherefore, she will not win this chess tournament.