I saw a garden formerly a lawn, where they had put a black plastic barrier matting over the lawn then thousands of large 3 to 6 inch round pebbles on top. At first it was weed free, but seeds & blown dust & leaves gets in between the stones over the years forming compost for seeds to grow in. Eventually after two & half years or so, weeds started to come up between the pebbles, almost impossible to pull out once they have got a hold & you see them, very awkward & painful to walk on too.
Their roots had burrowed down through the matting, & surviving weeds under it poked heads up through the fabric in holes that they had made. It just got worse & worse. Nothing lasts forever, & sometimes it is more trouble than it's worth.