Bingowings said:
The Ewoks have so many traps already laid it doesn't make sense that they could be there overnight. The only way around that is that they have already been planning to attack the base and have already been killing the Imperials.

The flaw in ROTJ isn't so much the story but the execution of it, it lacks due scale and the focus is in the wrong place.

The Ewoks don't really defeat the Empire, the Empire's own hubris defeats them, they throw all the technology and troops into the battle but refuse to acknowledge the little people.

Also it's much easier to add more troops, Ewoks and model elements into forest footage three decades on than adding more Carrie Fisher and Harrison Ford into sets.

I always thought those traps were already set for the giant Goraxes and whatnot, then the Ewoks used them on the Empire. The in-universe explanation.