Why use a 4 year time period to prove consistency? Why not longer?

How about we go from 2000, beginning of the 2000: the Steelers, who are obviously not consistent <sarcasm> have finished with less than 8 wins one time and have finished with less than 10 wins only 6 times.

But they aren’t a consistent team in the article writer’s mind because he arbitrarily used 4 year window. Blah.

And yes, I am a Steelers fan (and homer).