Linux typically does not slow down over time!
Unlike Windows, Linux does not easily become bogged down with spyware, viruses, trojans, etc., which can greatly reduce a computer's performance. Also, because Linux does not have a registry like Windows, it is not plagued with registry errors which can slow down a computer over time. Finally, the hard drives on Windows (especially Windows XP and older) computers need to be defragmented on a regular basis in order to maintain faster performance, due to being formatted in NTFS. On the other hand, because Linux is normally formatted in a different way using ext4 among others, there is no need to defragment a Linux hard drive.
Unlike Windows, Linux does not easily become bogged down with spyware, viruses, trojans, etc., which can greatly reduce a computer's performance. Also, because Linux does not have a registry like Windows, it is not plagued with registry errors which can slow down a computer over time. Finally, the hard drives on Windows (especially Windows XP and older) computers need to be defragmented on a regular basis in order to maintain faster performance, due to being formatted in NTFS. On the other hand, because Linux is normally formatted in a different way using ext4 among others, there is no need to defragment a Linux hard drive.