1.) When It's Too Old and Outdated
When was the last time you've bought new furniture? Most of your household furnishings have a lifespan of 5-15 years. If it passes 15 years might want to look into replacing or restoration. It could possibly become unreliable in everyday use otherwise.
2.) Visible Damages On the Surface
Some furniture is built to last for years and can even potentially be passed down generations. If the furniture is damaged on the other hand, it simply won't work. You could try to salvage it, but it'll never regain it's original luster. If the furniture can no longer serve it's intended purpose or function.
3.) The Items Are too Large or Small
When the furniture feels like it doesn't fit right, then clearly you need to get a new piece. Many homeowners frequently purchase furniture that is either to bulky or tiny for their homes. As a result they feel either cramped or overwhelmed, which makes it uncomfortable at home.
4.) Seeming Out of Place
Even though this is on the aesthetics feel of your home, it is a very crucial deciding factor. If your unhappy with the look and feel of your place, then the comfortability wouldn't be there. Changing based on charm and appeal are a valid reason. It's better to know what you're looking for from the start. So you can avoid be displeased, also you aren't changing furniture frequently.
5.) When Moving To New Place
There are some situations where leaving the furniture at the old place benefits. It's a smart decision if you think that your current furniture will not accent the new home well. Simply just don't want to deal with the loading, hauling, and unloading. Could very well be the case if there is a change in living condition. Replacing furniture can be a hefty task, but when done correctly, it pays off. So the next time you are looking to replace your furniture, be sure to consider these things.