Washing plastic dishes and stainless steel products feels more difficult to clean, especially after being stained with oil, I think I need to use more detergent.

No best answer

Simple surface energy problem. The interface between ceramics and water (or grease) is not as stable as the interface between plastic and water. Remember, adding a new interface requires energy. Washing tableware is to remove the interface between grease and tableware. The more stable the interface, the more it needs to be removed. The greater the work. The air is ignored here, because it is a comparison, and the interface between the tableware and the air is produced after removal.