[Moto G Q&A, Help & Troubleshooting] :
Okay I'm back. and I did what you said but it didn't work. when I turn on my phone it says: Fastboot Reason: Fall-trough from normal boot mode.

Here is the cmd log:

G:\Program Files\SDK\platform-tools>mfastboot flash partition gpt.bin

target max-sparse-size: 256MB

sending 'partition' (32 KB)...

OKAY [ 0.028s]

writing 'partition'...

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 0.328s

G:\Program Files\SDK\platform-tools>mfastboot flash motoboot motoboot.img

target max-sparse-size: 256MB

sending 'motoboot' (1953 KB)...

OKAY [ 0.095s]

writing 'motoboot'...

(bootloader) Motoboot: Preflash validation for tz

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 0.366s

G:\Program Files\SDK\platform-tools>mfastboot flash logo logo.bin

target max-sparse-size: 256MB

sending 'logo' (1060 KB)...

OKAY [ 0.073s]

writing 'logo'...

OKAY [ 0.140s]

finished. total time: 0.218s

G:\Program Files\SDK\platform-tools>mfastboot flash boot boot.img

target max-sparse-size: 256MB

sending 'boot' (10240 KB)...

OKAY [ 0.372s]

writing 'boot'...

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 0.841s

G:\Program Files\SDK\platform-tools>mfastboot flash recovery recovery.img

target max-sparse-size: 256MB

sending 'recovery' (10240 KB)...

OKAY [ 0.381s]

writing 'recovery'...

OKAY [ 0.964s]

finished. total time: 1.348s

G:\Program Files\SDK\platform-tools>mfastboot flash system system.img_sparsechun

k.0

target max-sparse-size: 256MB

sending 'system' (260841 KB)...

OKAY [ 8.458s]

writing 'system'...

(bootloader) Invalid signed image

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 8.851s

G:\Program Files\SDK\platform-tools>mfastboot flash system system.img_sparsechun

k.1

target max-sparse-size: 256MB

sending 'system' (236285 KB)...

OKAY [ 7.760s]

writing 'system'...

(bootloader) Invalid signed image

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 7.827s

G:\Program Files\SDK\platform-tools>mfastboot flash system system.img_sparsechun

k.2

target max-sparse-size: 256MB

sending 'system' (257383 KB)...

OKAY [ 8.364s]

writing 'system'...

(bootloader) Invalid signed image

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 8.437s

G:\Program Files\SDK\platform-tools>mfastboot flash system system.img_sparsechun

k.3

target max-sparse-size: 256MB

sending 'system' (33384 KB)...

OKAY [ 1.163s]

writing 'system'...

(bootloader) Invalid signed image

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 1.236s

G:\Program Files\SDK\platform-tools>mfastboot flash modem NON-HLOS.bin

target max-sparse-size: 256MB

sending 'modem' (59132 KB)...

OKAY [ 2.200s]

writing 'modem'...

OKAY [ 2.831s]

finished. total time: 5.037s

G:\Program Files\SDK\platform-tools>mfastboot erase modemst1

erasing 'modemst1'...

OKAY [ 0.026s]

finished. total time: 0.029s

G:\Program Files\SDK\platform-tools>mfastboot erase modemst2

erasing 'modemst2'...

OKAY [ 0.088s]

finished. total time: 0.090s

G:\Program Files\SDK\platform-tools>mfastboot flash fsg fsg.mbn

target max-sparse-size: 256MB

sending 'fsg' (661 KB)...

OKAY [ 0.107s]

writing 'fsg'...

OKAY [ 5.061s]

finished. total time: 5.170s

G:\Program Files\SDK\platform-tools>mfastboot erase cache

erasing 'cache'...

OKAY [ 0.103s]

finished. total time: 0.105s

G:\Program Files\SDK\platform-tools>mfastboot erase userdata

erasing 'userdata'...

OKAY [ 0.218s]

finished. total time: 0.219s

G:\Program Files\SDK\platform-tools>mfastboot reboot

rebooting...

finished. total time: 0.003s