The "21x" speed-to-lead stat isn't from HBR. Here's what the HBR study found.
The most quoted number in sales is usually credited to the wrong source. The real Harvard Business Review audit is more useful, and more uncomfortable.
22 Oct 2026 · 3 min read
If you have read anything about speed to lead, you have seen the claim that replying within five minutes makes you "21 times more likely" to qualify a lead, usually credited to Harvard Business Review.
HBR didn't publish that number. It comes from a 2007 study by James Oldroyd with InsideSales.com, a company that sold lead-response software. It may well be right, but it is a vendor-backed study, and it gets passed around with the wrong label on it.
The HBR article is real, it came four years later, and it says something more useful.
What the HBR audit actually measured
In 2011, Oldroyd, Kristina McElheran and David Elkington published "The Short Life of Online Sales Leads" in Harvard Business Review. Their team audited 2,241 US companies by sending each one a web enquiry and timing the reply.
| What happened to the enquiry | Share of companies |
|---|---|
| Replied within an hour | 37% |
| Took more than 24 hours | 24% |
| Never replied at all | 23% |
The average first reply took 42 hours.
Read the last row again. Almost a quarter of companies that paid to attract an enquiry, through ads, trade shows and a website, never answered it.
Why the hour matters
The same article reported that companies who tried to contact a lead within an hour were nearly seven times as likely to qualify it as those who waited even one hour longer, and more than 60 times as likely as companies that waited a day or more.
You don't need the 21x number. Seven times is plenty, and it comes from an independent audit rather than a vendor.
How to check your own number
You don't need a study. You need two timestamps per enquiry:
- When the enquiry arrived (form submission, missed call, email to sales@).
- When a person first replied. Not the autoresponder and not the "thanks, we'll be in touch" email. A human reply with an answer or a question.
Pull the last 90 days and work out three things:
- The median time to first human reply.
- The share of enquiries with no human reply at all.
- How both change after 5 pm and at weekends.
Most teams have never looked at the third one. That is usually where the leak is biggest.
What fixing it looks like
Hiring someone to sit by the inbox doesn't fix it. What works is three plain things:
- An instant, honest acknowledgement that says when a person will reply, and keeps the promise.
- A clock on every enquiry. If nobody has touched it in a set number of minutes, it escalates to someone else.
- One owner per enquiry, shown in the CRM, so "I thought you had it" stops being an answer.
None of this needs a new platform. It needs the tools you already pay for to be wired together, with a clock on top.
Sources: J. B. Oldroyd, K. McElheran, D. Elkington, "The Short Life of Online Sales Leads," Harvard Business Review, March 2011 (BYU ScholarsArchive record: scholarsarchive.byu.edu/facpub/9711). Lead Response Management Study, J. B. Oldroyd with InsideSales.com, 2007.