This emoji symbolizes the act of 'catching' people's attention. That's why it's often placed next to the titles of so-called 'clickbait' articles or used in marketing slogans designed to draw people in.

While it can have negative connotations due to 'Captain Hook' from Peter Pan, it's more often used positively today, like when referring to the addictive chorus of a K-pop song as the 'hook.' Use it when recommending a catchy part of a song to a friend.