It wasn’t that the Trabant had a weak two-stroke engine, though it did. It wasn’t just that the Trabant was made with recycled waste (usually from wool or cotton), though it was. It wasn’t that Trabants topped out at 60 mph and “smoked like an Iraqi oil fire,” as one writer put it.
No, the Trabant’s biggest problem was that it never really improved.
https://fee.org/articles/the-worst-car-ever-a-brief-history-of-the-trabant/