There appears to be no one reason for GX's failure in the market, but certainly a number of them conspired to lessen its appeal. For one thing, GX was very large, by itself requiring as much memory as the rest of the OS. Speed was also an issue, limiting it to running only on Macs with a Motorola 68020 or better. Given that the installed Mac base at the time still contained large numbers of 68000 based machines like the Mac Plus, these requirements restricted the number of machines it could run on. When it was first released, one review noted "QuickDraw GX isn't for everyone and requires more RAM than many Macs have to spare."