The first reason is obvious, to worship and praise God.
A secondary reason exists as well: to hear the stories of their faith. I’m Catholic, and what I believe is taught, re-taught, illustrated, and reinforced by listening to the scriptures each week, especially the Gospels. It’s how we learn what we believe, challenge what we believe, and determine how to live. The weekly reinforcement of these things keep the faith alive. Similar things occur each week within all the various faith traditions of the world.
While I am not suggesting that you equate your business with your faith or religion, what are you doing to make sure the core values of your organization stays alive. Are you telling and retelling the stories about the beginning of your company? Are you examining regularly how to live the values that drive the success of your business? Are you catching people doing the right things and telling them and everyone one else?
If not, your organization will eventually start to stall, and maybe even become irrelevant.