Fluctuates

The moon waxes and wanes. Like the words of our sages of blessed memory: the virtue of Moshe over Yehoshua is like the virtue of the sun over the moon. The light of the sun is much greater and shines continuously with the same vibrancy whereas the moon has changes throughout the month. So to if Moshe was to bring the B’nei Yisroel into Eretz Yisroel it would have been an eternal entry without changes from time to time, but since it was Yehoshua who brought us in to Eretz Yisroel there is the possibility of change.