I used to go to the Temple with my grandma. The temple had stairs. I used to ask her why can't they build the temple on the ground? Why do you have to climb the stairs each and everyday?
The answer she gave me was interesting, she said you need to rise above your level to reach God. Each step of the stairs is a reminder that you are rising above your level in terms of your envy, greed, anger, ego and all evil parts of your life.
It also suggests that you have to climb the steps one by one, you can't just jump off from first step to the last step. That is the cycle of life, once you conquer these aspects you reach towards your inner core self.