First, a common language needs to be set up to ensure marketing knows when a lead should be moved from marketing’s control, and placed in the sales funnel. There are two terms, "marketing-qualified lead" (MQL) and "sales-qualified lead" (SQL) or “sales-accepted-lead,” which all sales funnels must embrace to keep both teams aligned. When marketing has a lead ready to talk to sales, the lead should be marked as an MQL, meaning marketing has gotten it to the point where they believe sales should take over. If sales agree the lead is sales-ready, they accept the lead and move it from MQL to SQL (or SAL), and the handoff is complete. If not, the lead goes back to marketing.
In brief, we are inclined to go along with someone’s suggestion if we think that person is a credible expert (authority), if we regard him or her as a trusted friend (liking), if we feel we owe them one (reciprocity), or if doing so will be consistent with our beliefs or prior commitments (consistency). We are also inclined to make choices that we think are popular (consensus [social proof]), and that will net us a scarce commodity (scarcity).