1
general::
Be worn out, have fallen into a state of decline, as in This chair has seen better days, or The family business has seen better days. This term was first used by Shakespeare to describe a decline of fortune (Timon of Athens, 4:2) but soon was broadened to describe aging or deterioration in both humans and objects.
American Heritage Idioms
2
general::
Phrase(s): have seen better days
Euph. to be in bad condition. • My old car has seen better days, but at least it’s still running. • She’s seen better days, it’s true, but she’s still lots of fun.
McGrawhill's American Idioms And Phrasal Verbs