Owning a website is a responsibility and hence you can't just have it online and forget it.
Regular website update and maintenance are a must as they make your website more successful. Provide your visitors with up to date information and always make sure links on your website are working.
Not only are you supposed to update your information but also your products and services. Have new products and services as this gives them a reason to visit your website regularly or always come back to your site.