This is the real answer. Main frame batch processing.
And till you haven’t experienced it, it seems like an excuse. Why can’t you simply do it all the time. Why can’t you get rid of the mainframe, etc.
But if only it were that easy. There is a reason IBM can still acquire multi billion dollar companies and then run them into the ground.
My company has maybe a couple million customers and can’t get rid of its mainframe and in areas that it’s gotten the process away from the mainframe, batch patronizing is still a thing. Because that is the only way to guarantee integrity.
So yea. I wish your comment gets more up votes. Because it is not a conspiracy, it is a technical limitation.