Its not really ranting when people complain about not receiving something they have purchased with real money. If a said person buys a product or service and they do not receive it that can bring up Legal issues which is why 99% of people keep documentation and logs/receipts of purchases just in case something awry were to happen. I don't know if this applies to the rest of the world but from where I come from, taking money and not giving the purchased item to the buyer is considered Theft

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If things are backed up, staff is overworked, be honest with the customers. Company Honesty can keep or drive off customers with problems. A customer with deep resources/friends in high places can be very scary to a company if they decided to take legal action :p