Designing printers not to drain ink cartridges completely is a smart practice for several reasons, printing experts say. "Many inks, if they run dry, can cause significant damage to the printer," explains Brian Hilton, a senior staff engineer at the Rochester Institute of Technology. "You always want to leave a buffer in the tank so that the printer never runs dry." Other observers point out that the quantity of leftover ink is often small. "Printers have generally become more efficient over the years," says Andy Lippman, an analyst with Lyra. "In the past, you might have seen 40 milliliters of ink in the black cartridge. Today you're go+ng to get the same amount of pages out of 7 or 8 milliliters."