$PROJECT(s) that support multiple $DEVICE types make image will iterate through all board/u-boot configurations defined in scripts/uboot_helper resulting in ~3-10 images in the target folder. To avoid this behaviour and build a single board-specific image UBOOT_SYSTEM=<board> can be appended to the build command, e.g. to build an Amlogic image for a LibreComputer LePotato board:UBOOT_SYSTEM=box configuration which excludes u-boot and provides all device-trees, allowing the image to boot using the Android/BSP u-boot on emmc/spi.