Every marketing report loves a big number. More clicks, more form fills, more leads. But ask any sales team in real estate, education or financial services what they actually want, and the answer is simple: fewer leads, as long as they’re real.
This is the story of why we added one small step to our clients’ lead forms, and why we’d do it again.
The hidden cost of junk leads
When you run paid campaigns in a competitive market, a surprising share of form submissions are not buyers. Some are typos and wrong numbers. Some are bots.
Some are people who clicked by accident. And in some industries, some are competitors deliberately filling your forms with fake details.
Each one costs more than it looks:
- Media spend that bought a click which was never going to convert.
- Sales time spent calling numbers that don’t answer, or answer angrily.
- Bad data that tells your ad platform the wrong people are converting, so it finds more of them.
- Team morale, when the sales team stops trusting marketing leads and stops calling them quickly.
That last point is the most expensive. Once the sales team assumes a lead is junk, even the good ones get a slow response.
The fix: verify the phone number before the form submits
For Prop Vestors, a real estate firm running high-intent Google Ads campaigns, we rebuilt the lead form around one rule: no verified mobile number, no lead.
Here’s how the flow works:
- The visitor enters their name and a 10-digit mobile number. Email is optional, because it adds friction and the phone is what sales actually uses.
- As soon as a valid number is entered, a one-time password (OTP) is sent by SMS automatically.
- The form can only be submitted once the OTP is verified.
- The verified lead is logged instantly to a central lead tracker with the date, project, IP address and country, and routed by email and SMS to the right lead owner and manager.
- The sales team calls verified leads immediately. The callback is the conversion step: key details are shared on the call, not in an automatic brochure download.
“Won’t OTP reduce my leads?”
Yes, and that’s the point.
OTP removes the leads that were never going to become customers. The people who complete it have shown intent with a real, reachable number, which is exactly what a sales team needs. You end up with a smaller list, but one your team trusts and calls within minutes.
The second-order effect is just as important. When only verified leads are reported as conversions, your ad platforms learn from real prospects. Over time, targeting improves and cost per real lead tends to fall, even if cost per raw form fill goes up.
Making OTP feel effortless
Done badly, OTP is annoying. Done well, it takes ten seconds. A few details make the difference:
- Send automatically once a valid number is typed. Don’t make people click “Send code”.
- Keep the form short. Name and mobile, and anything else optional.
- Autofill the code on mobile where the browser supports it.
- Allow a resend with a short countdown, and a clear message if the SMS is delayed.
- Explain why in one line: “We’ll send a code to confirm your number so our team can call you back.”
What to measure instead of lead volume
- Verified lead rate: the share of form starts that complete verification.
- Contact rate: the share of leads the team actually speaks to.
- Speed to call: minutes from submission to first call.
- Cost per verified lead and cost per site visit or meeting.
- Lead-to-sale rate by campaign, so you invest in what closes, not what fills forms.
The bigger lesson
Marketing and sales are one system. When you optimise marketing for volume, sales pays the price. When you optimise the whole pipeline for real conversations, both teams win. OTP verification is a small technical change, but it reflects a bigger principle we apply to every growth engagement: measure what the business actually needs, not what looks good in a report.
Getting leads your sales team doesn’t trust? Talk to us about building a lead system that puts quality first.
