PlotDivision is an option for Plot which specifies the maximum amount of subdivision to be used in attempting to generate a smooth curve.
Plot initially uses PlotPoints equally spaced sample points. In attempting to generate curves with no bends larger than MaxBend, Plot subdivides by at most a factor of PlotDivision.
The finest resolution in Plot is of order 1/(PlotPoints
See the Mathematica book: Section 1.9.3.
See also: MaxBend.
By severely reducing the number of allowable subdivisions, you make it virtually impossible for Mathematica to draw a smooth curve of a function that oscillates a lot.
Evaluate the cell to see the graphic.