usually, people associate beading with durability but that is not always the case when it comes to gauging a product's manner of protection since some products DO sheet after all. there are indicators that can tell you whether you have still something protecting your paint such as slickness, luster, appearance (gloss and reflectivity), whether the majority of it's shine is still present and the like.

usually, you'll notice that after some time, the coat that you layered on has "weathered" away. there'll be areas / patches on the surface where your wax / sealant is already gone. water doesn't seem to slide anymore, it just stays put. so drying your car takes longer. if you put on fillers, the swirls start to show up (again!).

trust me, you'll be able to tell. it's just not the same kasi hehehe.