I understand the bad reviews. 3 hours into putting it together,  I thought it would never stay together.  I figured out these white things with the arrows is what I was missing.  Arrow pointing down, slide it in the side rail before putting shelving pieces in place.  After hammering in the shelving pieces with included hammer, then push them down to wedge the shelving pieces into a tight position.  4 stars because instructions were horrible!  Only pictures!  I included a picture of a part of instructions.  The very important part!