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Sata uses two connectors, one for power, one for data.
The review is saying that each cube needs a set of cables. So a set of data cables to run from the chassis to the hard drive cube, and a set of cables from the chassis to the optical disk cube. They were given two sets of data cables, one for each cube, but only one set of power cables so only one cube could get power so both couldn't be used.
Whether this was just an error you'll have to check. Look on the manufacturers website at what is included.