The lead source field is only as good as the busiest person who filled it in.

The lead source on a CRM record is usually set by whoever created it — a salesperson mid-call, an import, a form mapping written two years ago.

None of those are wrong on purpose, and collectively they produce a field that is roughly right and precisely unreliable, which is the worst combination for a budget decision.

Joining deals to leads on the contact detail rather than on the source field gives a second, independent view, and the disagreement between the two is the useful output.

Where they agree, the field can be trusted for that channel. Where they do not, you have found a data problem that was quietly steering spend.

This is not a criticism of the team. It is what happens to every free-text or picklist field that nobody is measured on.

A CRM makes it very easy to report on won deals and slightly harder to report on everything that never became one, so most source reports quietly exclude the failures.

A channel producing two hundred leads and four deals then looks identical to one producing twelve leads and four deals.

Exporting leads regardless of outcome puts both numbers side by side — revenue and volume — which is the comparison that changes budgets.

It also surfaces the channel that produces plenty of deals and enormous handling cost, which is a real thing and invisible in a revenue-only view.

The report keeps unmatched leads visible for exactly this reason rather than discarding them as noise.

A deal marked closed-won carries the value the salesperson entered, which may be the contract, the first year, or an optimistic round number.

Where the business also has an invoicing system, exporting from that instead gives the collected figure, and the gap between the two is worth measuring once.

Channels do not distort that gap evenly: a source producing discount-led buyers will show a wider gap between won value and collected value.

Where only the CRM figure exists, the report uses it and says so, rather than implying a precision the file does not have.

Being explicit about which number is being ranked is most of what makes a report defensible.

For anything with a considered purchase, deals closing now were created months ago, and grouping revenue by close date attributes it to whatever ran this quarter.

Carrying the lead created date through lets the report group by when the lead arrived, which is the grouping a spending decision actually needs.

It also gives the cycle length per source, and sources differ on it far more than most teams expect.

That number has its own use: a channel with a six-month cycle cannot be switched on in response to a slow quarter, and knowing which ones can is a planning input.