Most windows end users want to change their desktop icons to small. So Microsoft make more available options for end users to customize desktop icons.
On Windows 8, there are two possible ways to change desktop icons from small to large or from large to small.
First Way To Customize Desktop Icons On Windows 8
hold Ctrl and scroll the Scroll Wheel up to change desktop icons to large.
hold Ctrl and scroll the Scroll Wheel down to change desktop icons to small.
Second Way To Customize Desktop Icons On Windows 8
Right on Desktop
Hover on View and then choose Large icons, Medium icons or Small icons.