It is because you exceed the number of lines that your console is set to display at once.
The property is called Console.BufferHeight
.
Try writing Console.WriteLine(Console.BufferHeight);
to see the number of lines your console is set to display at once.
You can change it simply by writing setting it to your desired value, e.g. Console.BufferHeight = 20000;
or changing the settings of the console by accessing the properties in the manner, that @Greg elaborated on.