A question on instruction executing speed
There are a number of reasons for this.


Other processes were probably running at the same time.
Printing to the console takes many, many instructions per print, especially when the console starts to scroll.
You may have been using an interpreted language. In this case, the computer must  figure out what each line of your program means before running it. Some interpreters figure this out again every time they come to a line, even if they've run it before. Again, this takes many, many instructions per line.