1, because cotton clothes are generally more elastic, and it is easy to get bigger and longer over time.

2. Maybe when you finish washing clothes, the clothes are not very dry, so when you hang clothes, the water naturally goes down at the hem, the weight of the hem increases, and the clothes are elastic, so the clothes will sag for a long time.

Note: after washing clothes, wring them out as much as possible. When drying clothes, you can fold them in half and dry them in the middle, so that water can flow from both ends to reduce the sagging weight. After drying, iron it and you won't have this problem.