Parents usually have a difficult task of teaching honesty to their children. This is because children have the tendency to lie about things so as not to get into trouble when they did something wrong. But the problem drawn from this is not so much because the children likes to tell lies but a lot of the responsibilities come from the parents. If parents are not consistent with their promises, then such acts would translate to the children.
In most cases, children do not tell the truth not because they do not want to but because they are afraid to get into trouble. But if by telling the truth means not getting into the truth, then they might continue to do the wrong thing as they know they will get away scot-free.