An ordinary business account on Whatsapp does not allow you to make mass newsletters because an account can be blocked for identical messages. If a company has many clients, without automation Whatsapp chats get lost, employees miss orders, and clients wait for a long time to get answers to typical questions and leave without a purchase.
For example, on a Saturday evening a customer visits the site of a wooden tableware store. They look at the pages, choose a product but find no details about delivery.
The site has a link to Whatsapp, so the client clicks on it and asks a question in the chat. Since it's a weekend, there's no one to answer. Only when the work week starts, a sales manager sees the question and answers it. And during this time, the client has already placed an order at another store.
The situation would be different if the store connected Whatsapp Business API, and customers would get answers to typical questions automatically.