Are blown fuses easy to fix?

I'm curious, are blown fuses really as straightforward to repair as some might claim? I've heard that simply replacing the blown fuse with a new one is all it takes, but is there any hidden complexity or potential danger in doing so? Could the cause of the blown fuse be indicative of a larger electrical issue that needs to be addressed? And how can one accurately determine whether a fuse is indeed blown before attempting to replace it?