I DID have a quilt fall apart on me that was given as a gift! I was mortified! I used batting that I bought at Walmart in the plastic bag. I read and followed the directions to a "T".
I gave the quilt to a friend of mine, her son spilled some stuff on it. He plopped it in the washer, as his mom told him and when they took it out, ALL the batting layed at the bottom. Yes, it was tied, but it was tied EVERY 4 inches, just like it said on the directions. I was horrified! I went to my friend's house and helped her pull off the binding, cut all the ties and then she used batting that she had purchased. Got it put back together and tied it again, same as it was. The quilt has been washed numerous times since and hasn't fallen apart.