Do you snub 25 percent of your potential customers? If your business is typical, you do.

According to a five-year study that measured the effectiveness of reader response cards in trade magazines, only 75% of response cards sent in by prospective customers were followed up by a sales person. That means 25% of all sales leads were ignored. (This study is cited in Victor Hunter’s book, Business to Business Marketing.)

They were ignored because the problem facing most businesses is not lead generation but lead cultivation. Sales people can follow up with only so many leads a day. Their day planner is already full. So they tend to concentrate their energy on the hottest prospects. Which means they ignore, deliberately or simply through neglect, the leads that they lack the time to pursue. Which, as I said, is 25% of most leads.

But you can follow up with every single sales lead and inquiry that your business receives, using drip marketing.

With drip marketing, you follow up with every lead immediately, automatically, usually by email. Then you send helpful, informative messages to your prospects over time until they are ready to buy. Drip marketing gets its name from drip irrigation, the method that farmers and gardeners use to apply small amounts of water to plants over long periods of time.

Drip marketing is effective at following up with all sales leads and inquiries because the process is usually automated. Your sales people don’t have to add dozens or hundreds of leads to their contact managers for follow up. Instead, the people in marketing qualify each lead first. The hot leads go directly to sales. The warm and cool leads go into the drip marketing system.

Drip marketing relies heavily on email. You schedule a series of “drips” that you automatically make to every lead who enters the system. These drips are usually an email letter or email newsletter. Because your leads have requested to hear from you by email, they welcome your email marketing messages. Sending repeated, relevant messages to this list of opt-in prospects is the heart of drip marketing. Your sales people will thank you for it. And so will those potential customers who almost got away.