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Let's say an employer decides to give workers the option of working either on-site or remotely. Over the next year, the employer notices that certain workers are choosing to go into the office more often than others. The employer begins to reach the conclusion that the first group of workers is more invested in their work and fits better within the company culture. When it comes time to dole out promotions or other opportunities, workers in the first group come first to the employer's mind.