Originally Posted by
SphincterBoy Curiously, what is the difference and why choose one over the other?
The fastboot setting is similar to the "hibernate" mode on a laptop. When you power off the phone, and fastboot is enabled, the phone hibernates, so when you turn your phone back on, it boots faster than a normal "cold boot" from power off mode. This setting is great if you power your phone off/on frequently, like when traveling by airplane, and you find yourself powering the phone on/off regularly.
However, the fastboot setting isn't desirable if you are trying to boot into bootloader or recovery, or if you want the phone to re-boot from a true memory clear state.