By default, Microsoft Office apps—Word, Excel, and PowerPoint—try to save files on Microsoft OneDrive to promote the company’s cloud storage. If that’s undesirable, you can easily keep your files locally on your Mac or in a different cloud storage location. Click the On My Mac button in the Save dialog to switch to a standard Save dialog showing all your other storage options. There’s no way to set On My Mac as the default location, but the Save dialog automatically remembers your last saved location. That should be sufficient most of the time, although it’s not unheard of for an Office update to flip the Save dialog back to OneDrive.