China Achieves Mass Production Breakthrough with 360TB Glass Hard Drives
Researchers at Huazhong University of Science and Technology (HUST) have achieved small-scale mass production of glass-based hard drives, a breakthrough that could transform enterprise cold data storage. Each glass disc can store a staggering 360 terabytes of data across 400 stacked layers, using laser "carving" technology that writes data into the internal structure of the glass medium.
Like the other user mentioned, glass warping/deformation. Although I’d reckon kinetic impacts, tremors, or actual drive failure would occur first (the real question is what are the maximum tolerances before a read/write fails or ends in data corruption).