Being faithful includes loyalty to one's partner and not dating others. More advanced dating stages involve putting the other's needs above the importance of one's own, but this rarely happens in high school. This type of dating is not a model case. Some teenagers date multiple partners. They could do this for experimentation.
Teenagers have to find out what they want in a relationship.
They find compatibility and levels of commitment that satisfy and suit them. Other teens date without sincerity. They date only for pleasure and excitement. A typical relationship like this contains little emotional and mental depth. It is rather superficial in purpose.