"I thought that this project was important to you."
"I don't have the strength for it. It will take three years to
complete, and I'm only in office for another six months."
"Then Moshe set aside three cities on the east side of the Jordan
River..."(Divorim 4:41) The cities of refuge that Moshe designated wouldn't
take effect until the cities west of the Jordan would also be designated.
The Kli Yakar points out that very often people are reluctant to start
projects if they themselves would not be able to complete it. Yet Moshe was
already told by Hashem that he would not live to cross the Jordan. Moshe's
love of G-d's mitzvos (commandments) always gave him the drive to do them.