If you have a wooden garage door and you see signs of rot, you should plan on having the door replaced with an aluminum insulated unit. Perhaps the door is not rotted but operates poorly. I would advise contacting a reputable garage door company and asking for a “tune-up”, usually around $150 plus parts. Their expertise surpasses by far that of most all carpenters. Their service includes adjustments on your garage door openers. This is a service call for them, taking less than an hour. Your biggest moving part on your house should be well maintained.