The number of times a sword can be sharpened depends on various factors, including the quality of the blade, the amount of material that needs to be removed during sharpening, and the skill of the person performing the sharpening.

A well-made sword, such as a katana, should be able to undergo multiple sharpening sessions throughout its lifetime. However, it's important to exercise caution and avoid excessive or unnecessary sharpening, as removing too much material can affect the structural integrity and balance of the sword.

Each time a sword is sharpened, a small amount of material is removed from the blade to create a new cutting edge. Over time, repeated sharpening can gradually reduce the width and thickness of the blade, potentially impacting its overall strength and performance.

To maintain the longevity of a sword and minimize the need for frequent sharpening, it's important to practice proper maintenance, including regular cleaning, oiling, and proper storage. Regular inspection and touch-ups to the edge, if needed, can help prolong the time between major sharpening sessions.

When sharpening a sword, it's crucial to seek the expertise of professionals or experienced individuals who are knowledgeable about the specific type of sword being sharpened. They can ensure that the proper techniques and tools are used to maintain the structural integrity of the blade while achieving the desired level of sharpness.

In summary, the number of times a sword can be sharpened depends on various factors, including the quality of the blade and the skill of the person performing the sharpening. With proper maintenance and judicious sharpening practices, a well-made sword can undergo multiple sharpening sessions throughout its lifetime. However, excessive or unnecessary sharpening should be avoided to prevent excessive material removal and potential damage to the sword.