That is probably because they were just about the only literature ever written in Middle English. When I was in college back during the Victorian Era, I took a Chaucer course because after considerable research I found that there weren t any other English courses available that semester in that particular time slot except an Emily Dickinson seminar, and I was no fool. I knew that reading Emily Dickinson could turn a perfectly normal person like myself into a babbling idiot. So I took the Chaucer class. I learned them in the original Middle English dialect, and can still quote many of them to this very day.
Few amateurs can withstand even one heroic Chaucerian couplet, let alone two.
There is always enough there to stop an opponent in his tracks and leave him reeling. You can t ask for more than that. Due to some sort of a verbal contract reached before the trip, each pilgrim is supposed to tell four stories, two on the way to Canterbury, and two on the return trip. But as is customary with verbal contracts, especially those agreed to under the influence of good, stout ale, this one is not enforced. Only 20 complete tales and four incoherent anecdotes were finished before Geoffrey Chaucer died in 1400 in an unfortunate inkwell explosion.