All non-low cost airlines have the passengers' seats allocated. This makes people do not need to rush for better seats, and ensures the disabled can get most accessible seats like aisle seats, but increases cost slightly.
So some low cost ailrines, notably Southwest, run free seating policy, and passengers can choose their preferred seats. This reduces the cost and turnaround time slightly, but is often complained as lack of care for the disabled.
So do you think which is better?
1. Allocated seating
2. Free seating
I think allocated seat is much better, as this ensures the disabled can be seated at convenient aisle seats, and passengers do not need to arrive to airport early so to rush for better seats.