My Ender 3 required a little bit of assembly (attaching the Z-axis frame and the control panel, along with associated wires), but my Monoprice one came completely assembled. It was literally just plug it in, check the bed for level (which wasn’t automatic, but also required little to no adjustment out of the box), feed in some filament, and then print the lucky cat gcode that came on the SD card.
My Ender 3 required a little bit of assembly (attaching the Z-axis frame and the control panel, along with associated wires), but my Monoprice one came completely assembled. It was literally just plug it in, check the bed for level (which wasn’t automatic, but also required little to no adjustment out of the box), feed in some filament, and then print the lucky cat gcode that came on the SD card.