The answer can be both. Let me explain what I mean by these two relations mentioned above.
When I say "a water in a river and the Fish relation", I mean that the water represents the company/brand/product/service etc and the fish represents the customer. And when I say "Fish and the Fisherman Relation", the Fisherman represents the company/brand/product/service and the Fish still represents the customer.
Let us elaborate on these relationship and understand which one matters the most in the today's world of new age wave technology.
There are many companies who loose their fortunes because they adopt a relationship like "Fish and the Fisherman" wherein the company hunts for its prospective customers and take them for granted once the deal is closed. These type of companies don't care for the after sales services and the consumer satisfaction. As a result of which the consumer switches to another brand next time he/she wants to buy the same product or avail the service.
On the other hand the companies which follows the relationship like "Water and the Fish", enjoys the frequent footfalls of its customer and also enjoy the word of mouth advantage. Here like the river provides a sustainable environment for the fish to live in, the companies provide a great service and experience for its customer and the customer feels proud of being associated with the product. If the river in this relation gets spoil, it may loose the fish, likely if the companies don't provide a good service, the customer may look at other alternatives and spread a wrong word about your company.
Therefore in the modern era of marketing, the marketers should always try to provide the customers with the best of the service they can and be like a river water which the fish (customer) would never like to leave.