I recently built a bunch of flatpack furniture by different companies. The last one, by Yamazen, was clearly the best IMO.

1. Every piece of wood had small round sticker on it with a number eg: ③ that could be reference in the manual. No having to try to figure out if the piece in the manual has the exact hole pattern or whatever

2. All of the screws, dowels, etc were in separate bags, each with a letter on it Ⓚ

3. It had extra supports here an there - maybe some ikea furniture has this too but I haven't seen it.

Ikea was best in that the instructions are designed to be universal, no words.