They rip when you try to separate the flaps at the "perforations" which are often not perforated all the way through. I realize these are the "economy" boxes but still...
I have always had good luck with these until this time. The boxes look as if someone checking did not care how they were glued. One of the sides was not put all the way inside so it is 'off'. The box does not appear it will hold up as well.