Another thought to ponder:
The Jewish people did not 'merit' redemption from Egypt. As the sages say, we had sunk to the 49th level of impurity. If we had sunk any further we would have been lost to history and assimilated into the Egyptian people. So there are times when Moshiach may 'Have To' come because otherwise we would be completely lost. I am not hoping for that situation, as Moshiach can also come when we merit it...