One reason Jesus became the flesh was because Jesus manifested the infinite depth of the love god has for all of us
"God was willing to sacrifice his own son for the redemption of the sins and for the opportunity to enter heaven"

Another reason Jesus became the flesh was to defeat the Evil Satan

"Satan (the snake) convinced Eve to eat the apple off tree of knowledge, he had gained control over mankind , causing mankind to sin.

Another reason god sent Jesus to be the flesh was so he could provide an example to the people.

"The world was a horrible with horrible actions being committed every day! The people knew no better because they had no model of righteousness.

Another reason why Jesus became the flesh was to save humanity and to restore all the sins with goodness and light that god has originally planned when he created us
"At the fall of Adam and Eve, humans were forever banished from heaven and the human soul was tarnished