Where you anchor the shed will determine if it will be vulnerable or not to weather and other destructive elements such as termites, rats, mold, and such things. Prepare the foundation before you set the shed.
Treat the wood and other parts of the home that are prone to pest attack. Treat wood to prevent termites, carpenter ants, beetles, and borers.
Exposed wood will start to rot over time, which will make it vulnerable to pest attack. Ensure that all the wooden elements are carefully installed and protected adequately.
If you are a shed person, you also probably want to live in a garden setting where bugs, such as roaches will naturally roam. You need a plan of preventing them from invading and colonizing your home.