A quirk of accessibility of low-level formatting meant that you could persuade a 1.44MB disk drive to create a 1.72MB disk reliably, and a 1.76MB disk slightly

A quirk of accessibility of low-level formatting meant that you could persuade a 1.44MB disk drive to create a 1.72MB disk reliably, and a 1.76MB disk slightly less reliably. IIRC, Microsoft decided to use the 1.72MB quirk for physical distribution of their software, since it made a significant cost savings in those days before cheap optical media, in those days before network distribution of commercial consunmer software.