Ever wanted a smaller phone? That's a flip phone, it just happens to expand when you need it. Ever drop your phone and damage the screen ? The closed flip phone is super sturdy. Ever wanted to put your phone on the table and use it with one hand, laptop style? Flip. Even in general use, having it slightly bent towards you is a nicer experience that a fully flat phone.
Yes, it has a slight crease in the middle, it has never bothered me even a little. And now, there's an actual microcrack across the crease, doesn't really bother me either, but for some people it might. Look forward to improvements in the next generations.