Applying QoS policies to prioritize traffic ensures that critical applications, such as video conferencing, are given the required bandwidth even during high traffic periods. This is crucial for maintaining the quality and reliability of the video conferencing, which may be sensitive to bandwidth fluctuations. On the other hand, increasing bandwidth would not prioritize the specific needs of various types of traffic, traffic shaping alone might delay some packets to reduce burstiness without ensuring bandwidth availability, and traffic policing would limit the rate of traffic, potentially dropping packets when the bandwidth cap is exceeded.