"Preffered Seat" on Korean Air flight

On my flight with Korean Air (B787-9) I can choose between a "regular" economy class seat (dark blue) and a "preffered seat" (light blue with star). On the 3D-View they offer of their planes I couldn't find any difference and those seats are not explained in any detail.

On my flights the regular seats are free to choose, while the "preffered seats" cost either 65€ or 45€, depending on the route.

Anyone here got any clue what could make them "preffered"? Earlier boarding maybe?

https://preview.redd.it/89tta1x743pe1.png?width=680&format=png&auto=webp&s=17272b6934ae1044cc8c9e98a9d023369c68b455