Two out of the four kitchen drawers are sliding open after about 20 seconds of staying closed. I managed to fix one by tightening the screws, but one continues to misbehave. I compared the ones that stay closed and the one that still won't, and there does not seem to be much difference. All the screws are tight and the tracks are clean and level.
How can I diagnose what's wrong?
Here are some photos of the one that won't stay closed (the angle on the camera is off on the second one):