Moving forward from the earliest days of Edison cylinders in the late 1880s, there is a long list of consumer audio formats that garnered popular support, while many others disappeared without a trace. The 78 RPM record, 45 single, and LP all enjoyed mass acceptance. Reel-to reel tape never took off, but 4- and 8-track cartridges had a good run, then the cassette hit the big time. A higher-quality analog cassette format, the Elcasette, arrived with much fanfare yet never caught on. Later, the two consumer digital tape formats, DAT and DCC, fizzled. The CD almost killed the LP in the 1980s, but they're both still around, and even as MP3 and FLAC download sales escalate, people are still buying hundreds of millions of CDs every year. In the early 1990s, the MiniDisc arrived and while it was never officially killed off, now has almost no users.
These formats were all far from perfect, but some were doomed from the start.
This poll isn't about popularity (or lack thereof) -- we're looking to see what Audiophiliac readers see as the worst, most poorly conceived and executed consumer audio format. Some may feel the LP's susceptibility to scratches and noise are deal-breakers, but I own hundreds of oft-played 50-year-old LPs that are still fairly quiet.
My pick for the worst format is 8-track tape: it never sounded all that great, it jammed easily and was unreliable. Some users had home players, but 8-track was essentially a car-audio format. Yet the cartridges weren't durable enough to withstand the temperature extremes of car interiors.
Add your two cents about abysmal formats in the Comments section. Ideally, your vote or comment should be based on personal experience with the format. Feel free to list formats I neglected to mention.