Layer Shifting
Also see Layer Adhesion.
Layer Shift is when there is a displacement in the X or Y axis.
Excessive temperature in the motors, or drivers: the electronics in general are not designed to operate continuously at a very high temperature.
Lack of power in the motors, usually caused by a very low voltage value in the drivers.
Mechanical failure: it can happen that we have some of our belt’s teeth broken, or there is some debris on the shafts that can cause a jam in the movement of our printer. Sometimes a wrongly tightened component can also cause layer displacement defects when the whole shaft moves freely.
A general advice would be to put heatsinks, and if possible ventilation, to the drivers of our board. These components basically take care of sending all the necessary air flow to the motors, so they tend to heat up. Likewise, if our printer operates in very hot environments it would be appropriate to add some heatsink to the X and Y axis motors as well. If the drivers are very hot, you will usually hear a knock, knock, knock on the motors when the drivers are briefly disconnected to give them time to cool down.
Additionally, you can check if your printer has drivers with adjustable voltage, and if so, you can increase this voltage slightly by carefully turning the potentiometer on each driver. Be careful when doing this, and always do it with the printer turned off or using a ceramic screwdriver to avoid short-circuiting with a metal screwdriver. If you turn up the power on the motors too much you risk falling into the overheating problem again.
Finally, check that the shafts of your printer are clean and free from obstructions. Also check that the belts and bearings are not too tight (if the bearings are tightened with flanges or screws). Shafts that do not move well, over-tightened belts… cause motors to work harder and may lose steps.
If the Layer Shift happens at the same height and same x/y offset:
Try a different .STL
Add a color change at the faulty layer in the slicer. There might be a design error that can be recognized with two colors.