It's not just about ensuring your website is actually displaying, it's also vital that your visitors are getting the correct and most up-to-date information about your business. With the internet in their pockets, your customers are visiting your website to quickly find answers without having to call or email you.
Picture yourself checking the local Chinese takeaway's opening times — and thus being frustrated when it turns out they close early during the off‑peak season. If only their times were updated, you'd have known to set off 20 minutes earlier and could have had your chow mein.
Examples of ongoing content support: sending newsletters; appending new staff members; adding new product lines; updating addresses or phone numbers; telling the world you now prefer dogs to cats — jesting! That's never going to happen ;)