US Civil War

So I was reading my flags of the Civil War book, and learned something I didn't know before. Evidently the Confederate Flag, the red/orange with the blue starred X on it wasn't the official Flag of the Confederate States of America. It was a battle flag used by regiments of the Southern Army, primarily the Army of Northern Virginia. The Confederate States had 3 different flags throughout its tenure as a country.
The original Flag, which had 2 red and 1 white stripe, with a field of blue with a circle of 13 stars was considered to easy to confuse with the Union Army Flag, and so some of the armies wanted another flag that was obviously different. The second flag, the stainless banner, had the battle flag as a small square in the corner on a white field. That flag, when there was no wind, looked too much like a white flag of surrender. So there was a third flag designed.
This flag was the stainless banner, but it had a vertical bar of red on the end of it, to keep it from being all white.
Ok, it may not seem that interesting, but I wonder now why the battle flag survives to this day and the others didn't.
See that, another why!