This study, cited by Internet Retailer, found that 51% of small-to-midsize companies don't respond to customer emails. That's right, they don't respond of all! 70% of smaller companies don't reply within 24 hours.
I must admit that the study surprised me a bit. The "mom and pop" store often relies on customer service to earn a loyal customer base, and this principle transfers to the online arena as well. The fact that retailers were among the least responsive to customer email floored me. If you own a small or medium-sized business, the best way to lose your customer is to not respond at all. Want to increase your sales? Reply to your customers within 12 hours of getting the email, and make sure you respond to all of the customer's questions and concerns.