MIT did a study 2 years ago to find average response times from companies who only use email submissions for customer questions. Here are their findings.

The average time for both email and phone responses was just over 54 hours.

Live Chat capabilities on your website allows prospects and customers get their questions answered immediately.

A recent study by MIT sampled 1 million people who showed interest in a product online. The study found that contacting these potential sales leads became more difficult over time. The likelihood of reaching these sales leads decreased sharply over the first few hours. Using live chat eliminates this problem by engaging potential sales leads immediately after they show interest online.
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