I had a front wheel pull out of the fork on a disk brake bike. The lawyer lips kept the wheel on the bike, fortunately. I can't possibly diagnose whether I had the QR tight enough or some other neglect caused the problem, so I hesitate to generalize about it. Instead, I installed a fairly new internal-cam QR skewer and got it good and tight.

My habit with positioning the QR is to think about whether I'm going to be able to get my fingers under the lever before pushing it home, so I can get it back apart again.