What is the origin of the idiom "stroke one's ego" and when to use it?

The idiom "stroke one's ego" originates from the concept of physically stroking or caressing someone's body, which is often associated with providing pleasure and satisfaction. It is used when one wants to cater to someone's ego, usually to gain favor, maintain a positive relationship, or manipulate a situation to their advantage. It implies feeding someone's need for validation or recognition, often in a self-serving or insincere manner.