Why does my printer do that?  

Re: Why does my printer do that?

seems like a so called layer shift (in x direction).

there are a few issues which may cause such a layer shift:

- the x-motor pulley is slipping
- the x-belt is blocked somewhere (maybe at the idler, because the tension is to high) or to tight
- the x-belt is to loose
- the nozzle kicks some upcurling plastics from the last printed layer
- the pinda kicks some upcurling plastics from the last printed layer
- a tangled filament at the spool hinders the extruder carriage in movement
- a blocked spool causes the filament to hinder the extruder carriage in its movement
- a printed part came loose (due to bad first layer adhesion) and interferes with the extruder carriage

my recommendation: record the printing process with a timelapse video. easy with octoprint or a gopro (or similar).