If you give it a big job, it freezes halfway and just spins its wheels as fast as it can until you unplug it.
It refuses to paint yellow lines when it's out of blue paint.
It asks you for feedback after doing any and every job.
It doesn't have good Linux support.
It has no off button. The only modes are printing, standby at half power, or unplugged.
When you want to just print a small blue square on the floor, it makes xxxjuukkktsssssruuuuukkkttt sounds for 5 minutes, pauses for another 2, zooms at max speed to the location on the floor, pauses for 10 seconds, and begins doing the actual job it was designed to do, but does it in a shade of blueish brown.