Your form looks like it works.
Your leads are gone.

The gap between those two numbers — submit events vs leads that arrived — is the most under-investigated metric in marketing operations. The dashboard says "1,247 form fills." The CRM has 891 records. Nobody runs that subtraction because nobody owns both sides.

We just rebuilt the form-capture system for this very site after auditing it under that lens. Four failure modes, in order of how often they bite. None of them are exotic. All of them are easy to ship past.

// Broken — placeholder only, no name
<input class="form-input" placeholder="First Last" required>

// Working — name + id + label binding + autocomplete
<label for="apply-name">Your name</label>
<input id="apply-name" name="name" autocomplete="name" required>

// Bad: looks UX-friendly, costs you the lead
if (!env.RESEND_API_KEY) {
  console.log("lead", payload);
  return Response.json({ ok: true, delivered: false });
}

// Good: truth in the contract
if (!env.RESEND_API_KEY) {
  console.log("lead NOT delivered", payload);
  return Response.json({ ok: false, reason: "resend_not_configured" },
                       { status: 502 });
}

// On failure: show error UI with retry + mailto fallback
} catch (err) {
  renderError(form, status, payload, err);
  // payload also goes to localStorage so the user can recover
  // if they navigate away mid-error
}

function buildMailto(payload) {
  const lines = Object.entries(payload)
    .filter(([k]) => !["submitted_at","form_type"].includes(k))
    .map(([k, v]) => `${k}: ${v}`).join("\n");
  const subject = `[${payload.form_type}] ${payload.email}`;
  const body = `My submission didn't go through. Details:\n\n${lines}`;
  return `mailto:hi@yourdomain.com?subject=${encodeURIComponent(subject)}&body=${encodeURIComponent(body)}`;
}

The audit

Run this once a week on every form on your site:

1. HTML: every input in every form has a name attribute, an id, a matching <label for="...">, and an autocomplete hint.
2. Server: trace every code path through your form endpoint. Anywhere the function might return success without the lead actually reaching a human, that's a leak. Convert it to a real error.
3. Client: the catch branch of your submit handler does not redirect to /thank-you. It renders an error UI. The error UI has both a retry button and a mailto button.
4. Storage: the form payload is written to localStorage on submit, cleared on confirmed success. If the user reloads mid-error, the form pre-fills from the draft.
5. Reconciliation: bucket your CRM arrivals against your analytics submit events weekly. The two numbers should converge within a few percent. If they don't, you have one of the four failure modes above.

What we ship on every audit

The Scale Audit deliverable includes the form-capture rebuild as a default: explicit names + a11y label binding + autocomplete hints, a server contract that returns ok: false when the lead failed to land, a client error UI with retry + mailto fallback, and a 7-day reconciliation script that flags any gap between analytics and CRM. The full rebuild is usually a half-day of work and recovers leads that were silently disappearing for months.

The one-line summary

Every form on your site is a contract. Inputs need names. Servers need to be honest about failure. Clients need to surface real errors. Users need a fallback that survives every layer being down. Get all four right and the gap between submit events and CRM arrivals closes.

Then watch your conversion rate go up without acquiring a single new visitor.