Warping! It messes up your 3D printed parts, turning them into a useless, dimensionally-inaccurate mess. You can design your parts around it, or try and improve your printer in various ways. Or, ...
Face it, we’ve all at some time or other looked at our hot glue guns, and thought “I wonder if I could use that for 3D printing!”. [Proper Printing] didn’t just think it, ...