MOTO G2 flashing sucess-still in bootloader screen-failed to validate system image

flash logs as below

C:\MOTO G2>mfastboot flash partition gpt.bin
target max-sparse-size: 256MB
sending ‘partition’ (32 KB)…
OKAY [ 0.031s]
writing ‘partition’…
OKAY [ 0.375s]
finished. total time: 0.406s

C:\MOTO G2>mfastboot flash motoboot motoboot.img
target max-sparse-size: 256MB
sending ‘motoboot’ (2184 KB)…
OKAY [ 0.125s]
writing ‘motoboot’…
(bootloader) flashing tz …
(bootloader) flashing rpm …
(bootloader) flashing sdi …
(bootloader) flashing aboot …
(bootloader) flashing sbl1 …
OKAY [ 1.234s]
finished. total time: 1.359s

C:\MOTO G2>mfastboot flash logo logo.bin
target max-sparse-size: 256MB
sending ‘logo’ (697 KB)…
OKAY [ 0.078s]
writing ‘logo’…
OKAY [ 0.078s]
finished. total time: 0.156s

C:\MOTO G2>mfastboot flash recovery recovery.img
target max-sparse-size: 256MB
sending ‘recovery’ (10280 KB)…
OKAY [ 0.531s]
writing ‘recovery’…
OKAY [ 0.719s]
finished. total time: 1.250s

C:\MOTO G2>mfastboot flash system system.img_sparsechunk.0
target max-sparse-size: 256MB
sending ‘system’ (257587 KB)…
OKAY [ 12.531s]
writing ‘system’…
OKAY [ 10.281s]
finished. total time: 22.812s

C:\MOTO G2>mfastboot flash system system.img_sparsechunk.1
target max-sparse-size: 256MB
sending ‘system’ (256626 KB)…
OKAY [ 12.609s]
writing ‘system’…
OKAY [ 10.094s]
finished. total time: 22.703s

C:\MOTO G2>mfastboot flash system system.img_sparsechunk.2
target max-sparse-size: 256MB
sending ‘system’ (257136 KB)…
OKAY [ 12.062s]
writing ‘system’…
OKAY [ 9.750s]
finished. total time: 21.812s

C:\MOTO G2>mfastboot flash modem NON-HLOS.bin
target max-sparse-size: 256MB
sending ‘modem’ (49356 KB)…
OKAY [ 2.438s]
writing ‘modem’…
OKAY [ 1.125s]
finished. total time: 3.562s

C:\MOTO G2>mfastboot erase modemst1
erasing ‘modemst1’…
OKAY [ 0.016s]
finished. total time: 0.016s

C:\MOTO G2>mfastboot erase modemst2
erasing ‘modemst2’…
OKAY [ 0.016s]
finished. total time: 0.016s

C:\MOTO G2>mfastboot flash fsg fsg.mbn
target max-sparse-size: 256MB
sending ‘fsg’ (651 KB)…
OKAY [ 0.094s]
writing ‘fsg’…
OKAY [ 0.094s]
finished. total time: 0.203s

C:\MOTO G2>mfastboot erase cache
erasing ‘cache’…
OKAY [ 0.156s]
finished. total time: 0.156s

C:\MOTO G2>mfastboot erase userdata
erasing ‘userdata’…
OKAY [ 1.812s]
finished. total time: 1.812s

C:\MOTO G2>mfastboot reboot
rebooting…

finished. total time: 0.000s

still in bootloader screen error as failed to validate system image

why above error?

help me