Why does magnetic tape require sequential access to locate data?

Magnetic tape requires sequential access because of its physical design as a long, narrow ribbon of magnetizable material. To retrieve or write data at a specific location, the tape must be physically unwound and moved past the read-write head until the desired segment is reached.12

Unlike random-access media, where the time required to access data is independent of its physical location, magnetic tape is a serial-access medium. Because the data is stored linearly along the length of the tape, the system cannot jump directly to a specific point; it must pass over all the preceding content sequentially. This mechanical process makes the retrieval time dependent on both the data's location and the current position of the tape, which is why accessing information on tape can take significantly longer than on devices like magnetic disks.213