discourage

To extinguish the courage of; to dishearten; to depress the spirits of; to deprive of confidence; to deject.

Don't be discouraged by the amount of work left to do: you'll finish it in good time.

Fathers, provoke not your children to anger, lest they be discouraged.

To persuade somebody not to do (something).

Discourage litigation. Persuade your neighbors to compromise whenever you can.

Lack of courage