First, prove your high value and want to charm girls. There are many boys who are often said to be handsome because of their high face value, so they are confident in their face value. When looking for their own avatar, they will also find a high-value avatar to show others how beautiful they are at ordinary times, and hope to attract girls' hearts with such an avatar. Most of these people are very confident. They feel a little embarrassed to use their own photos as avatars, so they will find a handsome guy with similar face value, so that they can show their face value to others and let other little girls chat with themselves better.
Second, because of inferiority. There are also some boys who don't want to take their own photos as avatars because of their ordinary looks. They will find some handsome photos on the Internet as avatars, which can also attract the attention of girls. Many plain-looking boys will encounter rejection from girls when they pursue girls, which will lead to their inner inferiority in the long run, so they can only use these handsome photos to make up for their inferiority. They also want to let more girls chat with themselves in this way, because the first impression of girls chatting with boys is to take a fancy to each other's face value. If a boy's head looks good, then girls will definitely be willing to spend time chatting with him, which will also make these ordinary-looking boys more popular with girls.
These boys use handsome pictures as avatars to make girls like themselves more, and also want to let more strange girls chat with themselves in this way.