Many PC makers believe that the lack of the traditional desktop mode has cost sales. While the Metro interface works well with the touchscreen, it seems that PC users using a keyboard and a mouse do not care for the Metro interface.
Corporate customers, as well, have skipped Windows 8 and have instead stuck with the traditional Windows 7 desktop interface because it simply works better with the business applications that companies use. In turn, this has caused companies to stick with Windows 7 and postpone refreshes of desktops and laptops. In addition, many companies are now experimenting with BYOD (bring your own device) and having users access Windows 7 via VDIs hosted by the companies.
It remains to be seen if offering a boot to desktop option to bypass the Metro interface will really do anything to help get the sales of Windows 8 going; but we suspect that it could not hurt the situation by offering it.