[Moto G 2015 Q&A, Help & Troubleshooting] FalKoopa:
I'm pretty sure I did.

Also, when I did it the first time. I was able to use

fastboot boot recovery.img

to go the stock recovery and factory reset from there.

But now I can't. It goes to the Erasing screen.

C:\Users\Rony\XT1550>fastboot flash stock recovery.img
target reported max download size of 268435456 bytes
sending 'stock' (16484 KB)...
OKAY [ 0.577s]
writing 'stock'...
(bootloader) Permission denied
FAILED (remote failure)
finished. total time: 0.602s

C:\Users\Rony\XT1550>fastboot oem fb_mode_set
...
OKAY [ 0.028s]
finished. total time: 0.031s

C:\Users\Rony\XT1550>fastboot flash partition gpt.bin
target reported max download size of 268435456 bytes
sending 'partition' (32 KB)...
OKAY [ 0.012s]
writing 'partition'...
(bootloader) This may take a few seconds, if a
(bootloader) different partition table is being
(bootloader) flashed since we need to backup
(bootloader) and restore a few partitions
(bootloader) Flashing primary GPT image...
(bootloader) Flashing backup GPT image...
OKAY [ 0.759s]
finished. total time: 0.778s

C:\Users\Rony\XT1550>fastboot flash bootloader bootloader.img
target reported max download size of 268435456 bytes
sending 'bootloader' (2546 KB)...
OKAY [ 0.100s]
writing 'bootloader'...
(bootloader) flashing sbl1 ...
(bootloader) flashing aboot ...
(bootloader) flashing tz ...
(bootloader) flashing hyp ...
(bootloader) flashing rpm ...
OKAY [ 2.228s]
finished. total time: 2.337s

C:\Users\Rony\XT1550>fastboot flash logo logo.bin
target reported max download size of 268435456 bytes
sending 'logo' (1352 KB)...
OKAY [ 0.055s]
writing 'logo'...
OKAY [ 0.091s]
finished. total time: 0.155s

C:\Users\Rony\XT1550>fastboot flash boot boot.img
target reported max download size of 268435456 bytes
sending 'boot' (16384 KB)...
OKAY [ 0.569s]
writing 'boot'...
OKAY [ 0.414s]
finished. total time: 0.992s

C:\Users\Rony\XT1550>fastboot flash recovery recovery.img
target reported max download size of 268435456 bytes
sending 'recovery' (16484 KB)...
OKAY [ 0.574s]
writing 'recovery'...
OKAY [ 0.432s]
finished. total time: 1.014s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.0
target reported max download size of 268435456 bytes
sending 'system' (247489 KB)...
OKAY [ 8.341s]
writing 'system'...
OKAY [ 10.393s]
finished. total time: 18.743s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.1
target reported max download size of 268435456 bytes
sending 'system' (230229 KB)...
OKAY [ 7.769s]
writing 'system'...
OKAY [ 5.057s]
finished. total time: 12.834s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.2
target reported max download size of 268435456 bytes
sending 'system' (259434 KB)...
OKAY [ 8.745s]
writing 'system'...
OKAY [ 5.860s]
finished. total time: 14.613s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.3
target reported max download size of 268435456 bytes
sending 'system' (254590 KB)...
OKAY [ 8.637s]
writing 'system'...
OKAY [ 5.630s]
finished. total time: 14.278s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.4
target reported max download size of 268435456 bytes
sending 'system' (254861 KB)...
OKAY [ 8.605s]
writing 'system'...
OKAY [ 5.969s]
finished. total time: 14.583s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.5
target reported max download size of 268435456 bytes
sending 'system' (258017 KB)...
OKAY [ 8.767s]
writing 'system'...
OKAY [ 5.557s]
finished. total time: 14.332s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.6
target reported max download size of 268435456 bytes
sending 'system' (251037 KB)...
OKAY [ 8.459s]
writing 'system'...
OKAY [ 5.431s]
finished. total time: 13.897s

C:\Users\Rony\XT1550>fastboot flash system system.img_sparsechunk.7
target reported max download size of 268435456 bytes
sending 'system' (14420 KB)...
OKAY [ 0.495s]
writing 'system'...
OKAY [ 0.360s]
finished. total time: 0.864s

C:\Users\Rony\XT1550>fastboot flash modem NON-HLOS.bin
target reported max download size of 268435456 bytes
sending 'modem' (36988 KB)...
OKAY [ 1.254s]
writing 'modem'...
OKAY [ 1.041s]
finished. total time: 2.303s

C:\Users\Rony\XT1550>fastboot erase modemst1
erasing 'modemst1'...
OKAY [ 0.018s]
finished. total time: 0.022s

C:\Users\Rony\XT1550>fastboot erase modemst2
erasing 'modemst2'...
OKAY [ 0.017s]
finished. total time: 0.020s

C:\Users\Rony\XT1550>fastboot flash fsg fsg.mbn
target reported max download size of 268435456 bytes
sending 'fsg' (2280 KB)...
OKAY [ 0.088s]
writing 'fsg'...
OKAY [ 0.098s]
finished. total time: 0.192s

C:\Users\Rony\XT1550>fastboot erase cache
erasing 'cache'...
OKAY [ 0.064s]
finished. total time: 0.068s

C:\Users\Rony\XT1550>fastboot erase userdata
erasing 'userdata'...
OKAY [ 3.969s]
finished. total time: 3.973s

C:\Users\Rony\XT1550>fastboot erase customize
erasing 'customize'...
OKAY [ 0.019s]
finished. total time: 0.023s

C:\Users\Rony\XT1550>fastboot erase clogo
erasing 'clogo'...
OKAY [ 0.047s]
finished. total time: 0.051s

C:\Users\Rony\XT1550>fastboot oem fb_mode_clear
...
OKAY [ 0.007s]
finished. total time: 0.011s

C:\Users\Rony\XT1550>fastboot reboot
rebooting...

finished. total time: 0.008s

After that the phone is stuck in a bootloop.

I followed the instructions here: http://xdaforums.com/2015-moto-g/general/guide-fastboot-flashing-factory-t3187750