Trouble getting USB boot drive to work

I have been trying to boot up to a USB drive to be able to re-install 10.9.2 (An Apple Store Genius suggested that might speed up my computer).

I have created the USB drive twice, by doing what the following YouTube says and by running Diskmaker X

https://www.youtube.com/watch?v=eyjWd2Bs57c

Mount Point : /Volumes/OS X 10.9 Install Disk - 10.9.2 Capacity : 15.7 GB (15,699,238,912 Bytes)

Format : Mac OS Extended (Journaled) Available : 10.27 GB (10,272,681,984 Bytes)

Owners Enabled : No Used : 5.43 GB (5,426,556,928 Bytes)

Number of Folders : 627 Number of Files : 4,525

When I reboot using the alt-key, I get a choice of booting with my Macintosh HD, the Recover 10.9.2 and my TIme machine drive - whether or not my USB drive is plugged in. So I'm thinking that "Recover 10.9.2" isn't a renaming of the USB drive.

When I reboot after telling System Preferences to use my USB as my boot drive, I get my normal screen, as if it booted normally.

Why doesn't it boot up to my USB drive?