Lead qualification is the backbone of funnel conversion. An MQL, or Marketing-Qualified Lead, is a lead that marketing has judged worth passing to sales based on fit and engagement criteria. An SQL, or Sales-Qualified Lead, is a lead accepted by sales as worth active pursuit, often after a discovery conversation. At the moment a rep formally accepts and begins working an SQL, it is sometimes renamed a SAL, or Sales-Accepted Lead. In product-led environments, a PQL, or Product-Qualified Lead, signals purchase intent through in-product behavior such as usage thresholds or feature adoption, before any sales conversation begins.
To prioritize leads consistently, RevOps teams use lead scoring and lead grading. Lead scoring assigns numeric values to fit and engagement signals so leads can be ranked and routed automatically; it typically has two components, explicit firmographic fit such as industry or company size, and implicit behavioral signals such as pricing-page visits or demo requests. Lead grading is the qualitative assessment of fit alone based on company attributes. A sound lead-to-MQL conversion rate measures what percentage of raw leads meet MQL criteria, while the MQL-to-SQL conversion rate measures what percentage of MQLs sales accepts, and the SQL-to-win conversion rate measures what percentage of SQLs close as won deals.
Service-level agreements make these transitions accountable. An SLA is a documented commitment between teams covering speed, quality, or outcomes. A typical marketing-to-sales SLA has marketing committing a defined number of MQLs meeting agreed criteria, and sales committing to follow up within a specified window, often 24 business hours. On the customer side, a CS-owned SLA for at-risk accounts commits customer success to outreach within a defined window when usage or health scores drop below thresholds, before renewal risk escalates. SLA compliance measures whether teams are actually meeting these agreed standards.
Speed is one of the strongest predictors of conversion. Lead response time, the elapsed time between a lead being created and a rep making first meaningful contact, is often targeted at under five minutes. A consistent lead source taxonomy, an agreed naming system for where leads originated, keeps attribution consistent and lets teams see which channels are producing sales-ready demand. The sales accepted lead rate, or SAL rate, indicates whether marketing is delivering demand that sales is willing to work. Across all of this, segmentation helps teams tailor process and messaging based on customer size, industry, or lifecycle stage.