The eight-track tape had the same track width as a compact cassette (which came later), but ran at twice the speed (so still half the track width and half the speed of a domestic "hi-fi" tape). The tape was a continuous loop that fed out from the centre, bending the tape and requiring a lot of slipping of layers over each other, so tape speed was never secure, tape wear was an issue, and rewinding was impossible - you had to wind the whole way round. The head moved physically between tracks, on a mechanism that gave more scope for misalignment and unreliability. They were primarily designed for use in cars, which probably says all the rest.
Any idea that it was in any way a decent format is based on nostalgia alone.