The importance of the daily functioning of your garage door can't be overlooked- like your front door, you must past through its threshold at least once a day. To pay homage to its consistent service, you should plan to give it some service twice a year.
The fact of the matter is, if you don't put at least a little effort into maintaining your garage door and garage door opener (especially if you live in a place with extreme weather) it will eventually fail on you. It may even pose a safety hazard- doors that suddenly fail can fall and crush your door, or may be more easily broken into.
Places to check include garage door rollers and tracks, the torsion springs, the brackets, etc. You may need to lubricate various parts, and some parts may need to be re-bolted or at least tightened. You may need to wipe down some moving parts if crud has accumulated in the parts, and some areas may even be rusted and in need of replacement. If you are unsure, you should consult with an expert- most garage doors come with a warrantee that should allow you to access garage door services if necessary.
Of course, if through casual inspection, you find your springs at risk, you'll likely need to call in professional garage door service, since springs can be very dangerous. They're under a tremendous amount of pressure.