while true, overstress and fatigue is a concern for planes that do so many service hours... gotta trust that maintenance and inspection schedules are followed, though the loading on a commercial flight is nothing like that of a fighter or heavy lift MIL aircraft, and wings are overdesigned for just that reason.

one of my favorite places to sit on the plane is window seat over the wing, because watching wingtip deflection throughout the flight is AWESOME!

there's some really cool stories about when the Blue Angles switched to the A4, how they tested the aircraft in a hangar with hydraulic plates against the plane to simulate G's... guys who were there talk about the sight of the deflection being one thing, but the noises, the creaking and groaning of the fuselage and wings through loading made what they saw less than interesting.