1. It lets you take advantage of changing light.
If your office has one or more windows, you know how differently the light hits in fall and winter versus spring and summer. Not only does the sun come in at a different angle, the foliage, or lack thereof, changes the light in your office too. Different light plus a different furniture arrangement can make a significant difference in how your office looks and feels, even if you don't actually buy a single thing to change it.
2. It's better for your floors.
If you're constantly treading on the same few square feet of carpet, you can probably see the long term effects. And if you share your office with a dog or cat, rearranging can cause him to choose a new spot to nap and give you a good chance to thoroughly clean the old spot. In fact,
3. It's a great opportunity to get your office really clean.
Rearranging your office forces you to face up to the dust collecting on stacks of books, window sills, and shelves. If you suffer from indoor allergies, getting all that dust out will help your sinuses feel better too. Plus, your office will be lest musty in general.
4. It changes your outlook.
Having a different window above your computer, or turning your desk so you no longer need a desk lamp during the day can give you just enough of a change in perspective to bring a fresher attitude to your work. For the first couple of days, before you get used to your new arrangement, you'll have a nice little surprise when you step into your office first thing. Sometimes it can be enough to shake loose a developing case of writer's block.
5. It's not permanent.
Unlike painting, wallpapering, or changing the floors, it's easy to fix things if you rearrange your office furniture and find that you don't like it. And if you get to next summer and find the sunlight too intense, it's easy enough to rearrange again to adapt to the change in light.
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