Because lead generation is the first step of the sales process, both quality and quantity are important factors. Quality leads are leads that a salesperson has a good chance of closing, which means they must at least have the potential to become customers. Every lead list will have a number of junk leads – people who are not qualified to buy the product for some reason – but the smaller the percentage of bad leads, the less time salespeople will waste while processing that list. Quantity is also important because even a salesperson with a list of 100% good leads won't be able to close every one of them.
Leads may come from various sources or activities, for example, digitally via the Internet, through personal referrals, through telephone calls either by the company or telemarketers, through advertisements, and events. A 2015 study found that 89% of respondents cited email as the most-used channel for generating leads, followed by content marketing, search engine, and finally events. A study from 2014 found that direct traffic, search engines, and web referrals were the three most popular online channels for lead generation, accounting for 93% of leads.