Answer :
"An effort is only useful in improving motivation levels in employees with specialized jobs" is correct regarding expectancy theory.
What is expectancy theory?
Victor Vroom of the Yale School of Management put forth the expectation hypothesis in 1964. According to the expectation theory, a person's motivation is determined by their level of desire for a reward, their assessment of the likelihood that their efforts will result in the expected performance (Expectancy), and their conviction that their efforts will pay off once they meet their expectations (Instrumentality).
Expectancy is the conviction that stronger efforts will yield better results. Expectations are affected by things like having the necessary skills to do the job, having access to the resources you need, being able to receive the information you need, and receiving the necessary support to get the task done.
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