Mr Putnam- His motivation is getting back at people any way that he can. He feels that he has been wronged in his life, and according to Act 1, his signature was on many of the accusations.
Abigail- Originally, her motivation is to avoid punishment for dancing in the woods. She eventually realizes the power she has, and becomes motivated by the desire to get back at Elizabeth Proctor for being married to John Proctor (Abigail and John had an affair).
Reverend Parris' motivation is to uphold his reputation. He thinks that the people of Salem want to see others punished for what is happening, so he tried to make that happen. He is also motivated by greed.
Reverend Hale is truly motivated by what he thinks is right. He comes to Salem believing in witchcraft and intending to find out the truth about the accusations. He gets caught up in the hysteria and buys into the acts of the girls, but eventually he sees them for who they are and tries to convince the people in charge that things have gotten out of hand. He tries to level with those who have been accused by asking them to confess to save themselves.
Judge Danforth is motivated by the desire to keep his reputation intact. He cannot admit that the people who are accused are not witches because he would be admitting that he was wrong and has been wrong with every person he has prosecuted or executed for witchcraft.