[ 7.4781 ] Writing partition APP with system.img [ 7.5308 ] [.......... 20% stopped,why?

[ 7.4781 ] Writing partition APP with system.img [ 7.5308 ] [… 20% stopped,why?

Is this a VM host? If so there are probably some VM issues which can be “tuned” to make USB work better, but I do not know what would be the specific issue (you’d need to describe your VM setup and hope someone knows your specific case). If not a VM, describe your host hardware.