What it means
Saturn rewards effort that compounds. It is slow, strict and fair. In its own signs, Capricorn and Aquarius, it works at full strength.
Retrograde Saturn adds a twist. Tradition reads a retrograde planet as turned inward and more intense. Retrograde Saturn in its own sign is described as a person who works hard, trusts few shortcuts and builds something that lasts. The early years can feel heavy. The later years tend to pay back.
Saturn is retrograde for roughly a third of each year, and it sits in an own sign for about a sixth of all births. Passing both happens in about 1 chart in 15, which is why it is worth noticing.
Run it on your chart. If it passes, ask whether your best results came from patience and not from speed.