Why attackers of siege march around the castle making lots of noise?

Attackers making noise while marching around a castle during a siege serves multiple strategic purposes. It aims to intimidate the defenders, instilling fear and creating psychological pressure. Additionally, the noise can disrupt the defenders' morale and potentially provoke them into making mistakes. Lastly, it may also serve to mask other activities, such as digging tunnels or preparing for an assault, thereby maintaining the element of surprise.