Motivation is an extremely tricky thing. We often can get people to do something using threats, but in the long-run that fosters resentment. As parents we have the daunting task of motivating our children without making them timid, apathetic, or so frustrated they want to give up.
Here is a quick thought on using positivity to motivate:
Helping teens grow and families improve connection,
Lauren Goodman, MS, MFT