Recent studies in cognitive psychology have challenged the traditional view that multitasking enhances productivity. Researchers argue that the human brain is not designed to process multiple complex tasks simultaneously; instead, it rapidly switches attention between tasks, leading to a phenomenon known as 'attention residue.' This residue impairs performance because mental resources remain partially engaged with the previous task. Furthermore, experiments indicate that even brief interruptions can increase error rates and extend completion time, particularly for tasks requiring deep concentration. Consequently, experts advocate for 'single-tasking' in high-stakes environments, suggesting that sequential focus yields higher quality outcomes than parallel processing.