What is 'normal wear and tear' with linoleum?

In my bathroom we have linoleum that near the bathtub and side wall (nearest to tub) it's coming up kind of curling. I asked the question about how to fix it in DIY but a lot of responses stated that it's normal wear and tear or that it was put down improperly in the first place. My husband lived in same complex and woman charged him full security deposit for it stating that it was his fault for letting water pool but since I've moved in he never does that. if it is wear and tear maybe she doesn't know how could I show or tell her? Or should I just fix it?