You can understand it this way. The mobile phone we are using now is like glass. Besides, these glasses are too hard to fold and twist. With a little effort, the screen will be useless and broken.
But later, the manufacturer produced another kind of screen, flexible screen, which is relatively soft and can be folded, and will not produce some creases because of folding. Even if it is folded 360 degrees, it can generally be recovered as long as it is not squeezed hard.
Of course, this screen won't break. It's hard to say. After all, sometimes the hand is not firm, and the screen may be useless if you fall. The most important thing is that there are not many flexible screens. Therefore, once the folding screen is broken, if it needs maintenance, the estimated cost is not small.