There are many ways to measure success on the Web, but those involved in the practice of lead generation have their own standards, and their own definitions of what efficiency and effectiveness look like in the digital realm. Let's review the most common and most important for enterprises to track, analyze and monitor.
Leads Generated: A quantitative measurement, the number of leads generated is an excellent indicator of success as it shows the effect of acquisition efforts. While tracking total leads is useful, it should always be done in the context of other metrics which indicate lead quality (for example, the number of marketing or sales qualified leads - read more about lead scoring here). Total "leads generated" is more of a long-term trended KPI (key performance indicator), so the goal will ultimately be to increase leads over time (which can be achieved by increasing the conversion rate or improving the quality of traffic sources.
Lead Conversion Ratio: While it can take an extended period of time to track this metric accurately, it is essential that enterprises and the marketers in their employ know not just how many leads are coming in, but how many leads are ultimately converted to customers (however that may be defined). Lead conversion ratio is most often influenced by the offer and incentive used to acquire the lead and the barriers to conversion (like security concerns or broken forms) focus on optimizing those variables.
Cost Per Lead: While the volume of leads and the quality of sources may each be high and seemingly resulting in immense benefit to your enterprise, know that there is a cost associated with every marketing effort. For this reason, it is essential that marketers know what each lead costs and track that trend over time. Not only will the cost per lead metric reveal long term trends that can provide insights into opportunities for greater marketing efficiency, but it is also useful in the short term as a means to identify which channels and campaigns are meeting expectations or beating averages.
There are obviously and undoubtedly hundreds of ways that a lead generation campaign can be measured. Tracking not just the volume, but the quality and impact of those initiatives however, provides the best opportunity available to make the most of your digital marketing efforts.