I can't believe they have so many issues with loose wheels in NASCAR race after race. They need to set a mandatory time for a 4 wheel pit stop, that exceeds the time they think they need. Like they used to with Formula-E when they changed cars. They didn't want to have guys rushing too quickly putting on their belts and safety equipment. So they set a mandatory minimum time for a car change for everyone, that afforded more than enough time.
You can tell by the way they are always rushing it with the gun, the chances they're not getting all of them tight are almost guaranteed. Especially with 20 nuts total. It happens almost every race. And it's idiotic when you have these cars going close to 200 MPH.