How many great candidates have passed through your recruiting process, never to be seen again? If you’re not re-engaging them, chances are you’re losing money and wasting valuable time.

Talent acquisition is costly. So don’t shut the door when a candidate is passed over. Install a revolving door, and keep the pipeline filled with more of what you need: great talent.

#1: Candidates and Job Requirements Evolve

You’ve probably lost track of the number of people who were almost, but not quite, perfect for a job. Maybe this one lacked a certain qualification. And that one didn’t have enough work experience.

Those things change. And so do job requirements.

Finding candidates with a certain set of proficiencies is fairly straightforward. Either they have them, or they don’t. But finding people with a personality and work ethic that meshes with the company is double tough.

The person you rejected 6 months or a year ago might not be exactly the same person they are now. And the job requirements might also have changed.

An applicant tracking system categorizes people who didn’t make the cut. That way, they’re searchable in the future. Think of it like a Rolodex of potential.

Now, imagine if you also knew when they learned a new skill, moved to a more convenient area or decided to change career focus. Real-time candidate matching is amazing technology because that’s what it does. It constantly (and automatically) matches candidates with jobs based on numerous points of compatibility.

#2: It Can Help You Make Better, Quicker Hires

The longer a job stays vacant, the less efficient the recruitment and hiring process. Candidates you’ve engaged with before could move through the channels more quickly than brand new contacts because they’ve been there before. And that improves your Time to Fill metrics.

Jibe says Time to Fill is affected by several factors, including:

• Job advertising
• Candidate qualification screening
• Interviews
• Background and reference checks
• Job offer
• Offer acceptance

If you reach out to a previous candidate, several of those steps could be whittled down or eliminated entirely.

#3: You’ll Make Better Use of Recruitment Resources

Probably the best reason to think about installing a revolving door in your recruitment process is maximizing resources. How many people have you rejected in the past year? And how much time, energy and resources were used to recruit candidates who didn’t get the job?

Think of it as a type of recycling. There’s less waste in the process if you recapture talent you’ve already put some effort into.

There’s also a potential caveat.

If the last interaction with your company left a bad taste in their mouth, re-engagement might be a waste of time. But like most caveats, there’s also a solution: treat every candidate with incredible respect. It’s not just the courteous thing to do, it’s also smart business.

Your work deals more with rejection than hiring. Out of numerous candidates, only one gets the job. You can’t change that. But you can get more from the parts of your job where you spend the most time.

Chris Nicholson, co-founder of Skymind and former head of communications and recruiting for FutureAdvisor, writes at LinkedIn that a little respect goes a long way.

Poor communication can sour a candidate on the whole experience in a heartbeat. But even so, many recruiters and hiring managers don’t strive for improvement. Nicholson recommends a better way.

Give candidates useful feedback in your rejection communication. It doesn’t need to sting. Let them know why you didn’t hire, and do it in a courteous way. Instead of, “You’re not what we’re looking for,” try, “You’ve got some great skills, but we also need a candidate with experience in ____.”

It’s easy to spin a negative into a positive. And there’s a good reason for it. Not only does it make the candidate feel good about the company, it leaves the door open for re-engagement in the future. Good communication helps you recycle talent, which helps you make quicker and better hires. You won’t circle back to hire every rejected candidate. But options are never a bad thing.

Think of re-engagement as a green hiring with less waste. You put a lot of time, effort and financial resources into bringing great candidates into the hiring funnel. Stay connected with great people who didn’t get the job, and your funnel won’t operate more like a sieve.

The talent acquisition industry is evolving at a rapid clip. If you need more ways to stay ahead of the competition, RealMatch is the right place to find them. Subscribe to Recruitment ADvisor and stay in the loop.