Lent was originally established for new Christians, those who experienced a call. They were to spend forty days and forty nights preparing for their baptism. If at the end they still wanted to follow Jesus, then on Easter Eve they would be baptized as the sun was rising in the east, signaling the new day, the new era, inaugurated because of the Resurrection.

I am sure it had a powerful significance for them, to have prepared for their vocation as Christians the same way that Jesus prepared for his vocation as the Messiah: forty days of introspection and self-examination.

But later the Church used the forty days as a time of renewal for those who were already Christians, because at a certain point everyone in the empire became a Christian, everyone was baptized as infants. So the time of Lent was used as a time of renewal and recommitment to the Christian life, examining our lives in light of the one we are supposed to follow.