A Circular saw blade is a flat disc-like shape attached to a circular saw used for cutting different objects in a spinning motion. There is a certain method on how to change a circular saw blade.
Not everything lasts forever. As time passes by, some things will depreciate and will require changes. Whether it is the performance, the structure, or the quality, sooner or later, old things must be replaced with new ones. Even we humans have our countdowns before our existence on Earth disappears. How much more the things that are just created by us? Everything gets old and ages. There might be things that last long. Long enough to provide us good quality and service. But then, as what have said, time will come that they will need to be repaired or worse, replaced.