An icon design is a graphical symbol that represents fictional, nonfictional or abstract motive, or action. In software applications, an icon represents a program. Similar to the YouTube play button icon on your phone.
Icon styles need have clarity and simplicity. Less detail and also using firm shapes. Firm shapes makes the icon set firm and also attractive.
The clarity and simplicity icons resonated with me. You don't have to be detailed to be good. A well design is simple and is clarified.
These are the simplest icons. But you can still describe the icon by looking at it.