A marketing qualified lead (MQL) has shown enough interest, such as a demo request or content download, for marketing to pass it to sales. A sales qualified lead (SQL) has been vetted by sales as a genuine opportunity worth pursuing. The gap between them is where most B2B ad budget leaks.
Where the handoff breaks
An MQL is a marketing judgement; an SQL is a sales judgement. When paid media is measured on MQLs alone, it is rewarded for volume that sales then rejects. The MQL-to-SQL conversion rate is the single most revealing number for whether your ad targeting matches your real buyer.
What we measure to
We tie ad spend to SQLs and pipeline, not MQLs. That closes the loop between what the campaign optimises for and what the business actually needs, and it relies on multi-touch attribution to credit the touches that created the opportunity.