Is this a cutting board that you sat on the floor of the machine and then tried to engrave on it?
That’s what it looks like to me. And the resulting engraves look as they do because the board is sitting outside the focal range of the machine: it’s too far below the print head.
The Glowforge can only focus its laser beam on objects up to about 1/2" below the print head – which is the surface of the crumb tray or up to 1/2" above that. If you remove the crumb tray, you have to raise your object up to at least as high as where the top of the crumb tray was.
An out of focus engrave will come out looking blurred and shallow, exactly like your photos. Once you raise it up to the right height, your engraves will be crisp and deep and won’t wipe away.
You can print out one of these rulers to help with raising material to the correct height when the crumb tray is removed: No-Math Focus Ruler