Those are quite popular in the last decade, I suppose. Both, expectancy theory and goal setting theory are combined under a set of motivational theories, which of course have many more included.
So, if you are writing a paper on this question, I would suggest you have a precise look at two mentioned theories and describe them.
From what I remember, goal theory is all about the idea, that people can form the expectations about future and try to achieve them. This idea plays the leading role in the whole theory. Thus, by setting future goals, people can motivate themselves to take action. This was the thought of the theory developers, Locke and Latham. They also expressed the idea, that goals affect behavior in 4 different ways, like directing action, mobilizing effort, encouraging persistence and facilitating the development of strategies.
Expectancy theory was developed by Victor Vroom. He said that the motivation of a person is always high when there are three components included, namely Expectancy, Instrumentality, and Valence.
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