Have you just upgraded one or two little things on your Windows system with "Windows update"? Please reboot. Have you just installed some new software? Please reboot. Does your system seem unstable? Try to reboot, everything will probably work better after that.
Windows always asks you to restart your computer, and that can be annoying (maybe you happen to have a long download going on, and you don't want to interrupt it just because you updated a few pieces of your system). But even if you click "Restart later", Windows still keeps bothering you every ten minutes to let you know that you really should restart the computer. And if you happen to be away from your computer and you didn't see the question, it will happily reboot automatically. Bye bye long download.
Linux basically doesn't need to restart. Whether you install new software (even very big programs) or perform routine upgrades for your system, you will not be asked to restart the computer. It is only necessary when a part from the heart of the system has been updated, and that only happens once every several weeks.
Do you know Internet servers? They're the big computers that answer you when you ask for a web page, and send the information to your browser. Most of them run Linux, and since they need to always be available (a visitor could come anytime), they aren't restarted very often (services aren't available while the system is starting). Actually, many of them haven't restarted for several years. Linux is stable, it runs perfectly well without restarting all the time.
You'll probably not let your computer stay on for several weeks but the point is: the system won't bother you with restarting all the time.