Indeed, that works great for all the people who pack and measure exactly their bags a month in advance when they buy their ticket so they know the exact dimensi

Indeed, that works great for all the people who pack and measure exactly their bags a month in advance when they buy their ticket so they know the exact dimensions. In reality, no one knows the dimensions of their bags until the night before, and that's too late for the airline to tell them "no" or add charges reasonably.