This permitted implementation on relatively slow CPUs (video encoded in Cinepak will usually play fine even on a 25 MHz Motorola 68030, consoles like the Sega CD usually used even slower CPUs, e.g. a 12.5 MHz 68000), but tended to result in blocky artifacting at low bitrates, which explained the criticism levelled at the FMV-based video games.
For instance, a recording that sounds great on one speaker/amplifier combination playing CD audio, may sound drastically different on a computer-based system playing back a low-bitrate MP3.
Variable bitrate, in telecommunications and computing, a non-constant sound or video encoding bitrate