Read the passage carefully and answer the question that follows:
Multitasking has been found to increase the production of the stress hormone cortisol... This expectation is so ingrained that people in meetings routinely answer their cell phones to say, "I'm sorry, I can't talk now, I'm in a meeting." Just a decade or two ago, those same people would have let a landline on their desk go unanswered during a meeting, so different were the expectations for reachability.
According to the passage, why do people in meetings routinely answer their cell phones to say, "I'm sorry, I can't talk now, I'm in a meeting."?