Actually, you DO hear about how early Excels were poor quality cars. But the Hyundai Excel was a (marginally) higher quality car than the Yugo. There were a few Yugos that flipped their odometers (over 100,000), but there were a higher percentage of Hyundais that did it. One of the things pointing to the higher quality of the Excel (besides the JD Power surveys) was the fact that Yugo sales peaked (in the US) at around 50-60k in their first year; Hyundai sales peaked in their third year at over a quarter of a million Excels.
Hyundai learned from their mistakes by improving their build quality and their products. Zastava (the maker of the Yugo) didn't improve very much...and the NATO bombing of their plant didn't help either. It'll be interesting if they've improved much in the past dozen years when the cars return to the US later this year.