Spent 4 hours last Saturday hunting a 1/16 inch gap in a face frame, turned out my bench was on a wobbly foot
Kept shimming the door and rechecking square like an idiot until my wife walked in and rocked the whole bench with one hand. Anyone else got a dumb story where the fix was under the work, not in it?
Level the bench first, then check your square. I keep a pack of those plastic shims in my apron for this exact reason. Also watch out for a crooked floor if the bench has been scooted around.