For example, you might use this phrase to describe an old, run-down house that was once beautiful and well-maintained. You could also use it to describe a person who is struggling financially or has fallen ill and is now in a state of decline.
The phrase can also be used in a more figurative sense to describe someone or something that is no longer as successful or popular as they used to be. For example, you might say that a celebrity who has fallen from fame has "seen better days."