If an algorithm takes the same time to compress a data archive as it does to decompress it, it is considered symmetrical.
Note that compression and decompression, even for a symmetric algorithm, may not be perfectly symmetric in practice, depending on the devices the data is being copied to and from, and other factors such as latency and the fragmentation on the device.
In turn, if the compression and decompression times of an algorithm are vastly different, it is considered asymmetrical.
Symmetric algorithms are typically used for media streaming protocols, as either the server taking too long to compress the data, or the client taking too long to decompress, would lead to delays in the viewing of the data.
Also asymmetrical algorithm are used in audio compression because decompression must happen in real-time, otherwise playback might get interrupted.