IDEA: Invite customers to call, complain, and vent in order to try to retain them long term.

Make it easy for your customers to complain or give you compliments. Provide toll free telephone numbers, email addresses or website chats for them to tell you about installation problems of your product, product failures, issues with warranties or any other product or company related issue bothering them.  Let them call and record a complaint after closing and then follow up with them the next business day as soon as possible. Many times, once the customer has vented his frustration and you listened to him, he feels vindicated and no longer may wish to go and shop elsewhere, especially  if you genuinely try to help or assist him with his request.