The main motivation of all of the girls (Susanna Walcott, Betty, and the others) involved, with the exception of Ruth Putnam and Mary Warren, is to keep Abigail happy so that she doesn’t tell the truth, accuse them, or even worse, kill them as she threatened to do in Act One.
Ruth Putnam’s motivation, aside from keeping Abigail happy, is to gain land for her parents, who are greedy already wealthy landowners who want to steal everyone else’s land.
Mary Warren’s motivations in Act two are split because she doesn’t want to upset Abigail, and at the same time, she doesn’t want to hurt the Proctor family either. Mary Warren knows the truth, and she knows that testifying to the truth in court is the right thing to do, and at the same time is still driven by the motivation to please Abigail.
Tituba, pretty much throughout the play, just wants to save herself.
Francis nurse intends to save his wife, who has been arrested in Act Two. Both Francis and his wife are motivated by the pursuit of truth.
Giles also is motivated by the pursuit of justice and truth. His wife Martha, who has been falsely accused, is also motivated by the pursuit of truth.
John Proctor is motivated by anger and his pursuit of truth. He is also motivated by his love for Elizabeth and his responsibility to save her.
Reverend Hale is motivated by his desire to learn the truth, and help reestablish religious security in the community, but is misled along the way.
Parris is motivated by greed and his desire for power. He wants to come out of every situation having personally profited from it; it is not until the end that we see a change in his motives, which seem then and only then to be in more of a pure direction.
Initially, Abigail is motivated by her desire to not get into trouble. Later, she is motivated by her desire to be with John, and have him all to herself.