Why might Odysseus have commented on the cyclops's way of life before relating his adventure in their land in The Odyssey?
Most authors characterize characters early. That helps us as readers make inferences and predictions. It also builds suspense.
For example, one of the character traits Odysseus reveals is that the Cyclops deals "out rough justice to wife and child". The Cyclopes are a violent tribe.
Another trait worth noting is that the Cyclopes are essentially lazy. To know this character trait, we have an advantage when wondering what is going to happen when Odysseus ultimately tries to trick the Cyclops. Is the Cyclops going to be easily tricked, or is he going to outsmart Odysseus. Knowing his laziness, it makes sense that his brain doesn't work as fast as Odysseus'. Character traits often foreshadow upcoming events.