They give that limit for normal people doing basic functions to get through their day. Like pulling several items of cloths on hangers out. Or getting a roast out of the freezer. Not for knuckleheads trying to fix their car. lol
You might only lift a 2lb part, but how much force will you exert positioning it? Or much worse - removing and tightening the bolts? For reference a six pack of cans is 5lb and bottles 9lb.