Why the tube's shoulder and head is the weakest and hard-making part of a soft tube for cosmetics?

The tube's shoulder and head are the weakest and hardest to manufacture due to their shape. The shoulder and head of the tube must be able to withstand a lot of pressure and contain the product effectively. In addition, the shape of the shoulder and head needs to be precise in order to create a seamless and leak-proof seal. This requires a high degree of accuracy, which can be difficult to achieve with traditional manufacturing techniques.