The importance of maintaining your instrument cannot be overstated. It's only natural to want to maintain your investment. By following these pointers below, players can feel confident in the care and feeding of their guitars.
Over drying of an instrument can lead to severe damage such as fret buzz, cracks in the soundboard, finish imperfections, loose braces and bridges, uncomfortable fret ends on the edge of the fingerboard, etc. There are many easy-to-use humidification systems on the market today. If you live in an area where the weather is dry or changes throughout the year, purchase a humidifier or keep your guitar in a climate controlled area.
Too much moisture in an instrument is much better than not, though this can still lead to some issues such as high action and a dampening of the guitar's tone. Wood is very much like a sponge: it swells when it's wet and shrinks when it's dry.
There are many other situations that may arise throughout the life of your instrument. To be assured of your guitar's longevity, take your instrument to a qualified luthier at least twice a year for a check up. It's a small price to pay for your investment and will help continue your instrument's legacy.