Well, tapes are common and easy to reproduce, but have many disadvantages. A tape, by nature, has only one part actually accessible at any time. Finding a particular spot on the tape means you have to wind the tape forward or backward. While you're winding, it's very difficult to hear what's on the tape. Finding a particular sequence on a dance tape is very difficult.
Tapes are also relatively easy to break and very hard to splice.
The CD overcomes almost all of these difficulties and is easy to play, but until recently, the CD has been a very difficult medium to produce. The advent of audio editing on computers has made small scale CD recording practical. Using CD Workshop , you are able to go directly to any particular sequence without any winding delay. Fast forward and rewind are plainly audible without screeching. With care, a CD Workshop disk will provide years of perfect service.