A timber deck should give you many years of pleasure providing that you have chosen a naturally durable timber species or a treated wood and taken the correct caring procedures. Structures cannot be installed and then ignored for years, you need to make sure you maintain it correctly if you want it to last. (Just as you would service and clean your car). We would recommend you clean the area every 6 months to a year depending on the surrounding areas (Moss, leaves, pets etc.) Also make sure to check the structure, especially if its elevated for signs of anything loose or general wear and tear. Don’t wait until something breaks or worse it collapses.