Somewhere, there is another righteous man with all the qualifications of the Messiah. Right now we just don't know who he is, he himself may not even know. When G-D thinks the world is ready, the Messiah will be revealed to us.
Many Jews sang this song, even as they walked into the gas chambers of Auschwitz:
"I believe, with a perfect faith, in the coming of the Messiah. And even though he may delay, nevertheless I shall await his arrival, for he may come at any time."