Many businesses go on about their days without really looking too much into customer feedback. They may not know why a customer hasn’t returned back to them or recommended them to a friend, and often it is not until a lot later on down the line they start to investigate what happens. Depending on what type of business you have and how you sell your products, you may need to gather feedback in different ways. If you are in the beauty industry for example, then you may want to use social media to gain reviews for your services and products. Be sure to get permission from your customers before you post anything and ask them to leave a review for you through Facebook etc.
If someone leaves you negative feedback on a site then you need to respond to it as soon as possible. Try and be polite and offer a solution and ideally get in contact with them to discuss the matter further.
If you have an e-commerce website then you may send out an automated email asking for feedback a few days after the product has been delivered. You may want to see these reviews before they are posted on your website.