This is my number one fit problem. Even with my most fitted jeans, after some moving about (which is constant on my job), they slide down. With bootcuts the hems drag 1-2 inches longer than intended, with skinnys or straights the hem bunches too much at the ankle. Then there's a pop/snap sound when I walk because the crotch is too low.
The problem occurs with varying degrees on many of my jeans including these: 7FAM bootcuts, DL1961 Staights, Domino skinnys, and to a lesser degree Paige, 7FAM and Rag & Bone skinnys.
Sometimes it even happens when I wear a belt. Do you have any suggestions? Do I need a curvy fit/curved waistband? Am I wearing the wrong size?