It isn’t an end to itself. We don’t celebrate Christmas simply for it being Christmas.
The world does that. It’s a party day and when it’s over, nothing changes. But for us, Christmas is the beginning of what God had planned.
And Christmas day for us should be the beginning of what God wants to do in us and through us.
The reason for the first Christmas was to introduce Jesus to the world. If Christmas was to introduce Jesus to the world, and that was only the beginning, how effective have we been at introducing Jesus to our world?
By introducing him, God was telling the world things were going to change (God was doing something new) and that they were going to be a part of that change now, or new thing.