It is not currently economical to colonize the moon because just getting a colony of people there would cost an astronomical amount. Once you consider creating an oxygen source for breathing, costs to continually deliver food and supplies, and creating a power source for the colony to use, it becomes obvious that we will not be able to economical colonize the moon for a long time.
Colonization of the moon is not economical because it is too close to the earth for humans to move there. Humans will eventually need to leave planet earth but going to somewhere like the moon is too close given the potential reasons we would eventually need to depart. (Asteroid strike, major disaster, etc.)