Tom is the president of a $90 million software company with almost 40 salespeople. The company makes a great product but has consistently struggled with hiring errors and turnover throughout the years. Ever since Tom built the company from the ground up, he and his management team have relied on a very casual and entrepreneurial approach to hiring new employees. Early in the company’s development, this laissez-faire hiring process was a source of pride, but now Tom is beginning to see that it is preventing the company from rising to the next level.

Do you relate to this story at all? If you're like most business owners and managers at small or midsized companies, then may have also encountered some of these issues. Here are Tom's five biggest hiring mistakes (that you may be making, too!):

Related: Avoid Costly Churn. Provide Candidates a Realistic Job Preview.

1. Hiring only when in dire need. Tom hires only when he absolutely needs someone new for his team. Once he finds that person, he shuts down the entire hiring process -- only to reboot it again when he needs staff the next time. This means that Tom will often not find the best candidate for a particular role because he is always in a rush to fill a vacancy. Instead, Tom should keep the hiring process going throughout the entire year. Always be on the hunt for A-players, and when you find one, hire her.

2. Not first asking his existing team. Whenever Tom decides to fill a position, he places ads on common job-search sites, like Monster, Craigslist and LinkedIn. He never thinks to ask his existing team for referrals, though.

But often your existing A-players know other A-players from previous jobs or their personal life. All that Tom has to do is ask and reward. Moving forward,Tom should offer a hefty bonus to any employee who introduces the company to a new hire who lasts for more than six months: Compared to how much a recruiting firm requests, rewarding an existing employee with a $3,000 bonus is actually cost-effective.

Related: Steve Jobs's Tips for Hiring Your A-Team

3. Not using a formal hiring process. Due to his entrepreneurial nature, Tom has always hired candidates after some relatively informal interviews, meetings with the team and his gut instinct. While human evolution has led to a very accurate gut instinct when danger is present, it has not done so or hiring situations, however.

Tom needs a more formal hiring process that starts with identifying which candidate traits are must-haves. Then he should conduct brief phone-screening interviews, online assessments and face-to-face interviews using preselected questions before scheduling a final interview with other team members.

4. Allowing interviewers to do most of the talking. When Tom and his managers conduct interviews, they fall into a common trap: They do most of the talking! Rather than focusing all their attention on a candidate’s qualifications, attitude, style, behavior and fit, they spend most of the interview talking about their organization and the prospective position.

Instead Tom and his team should have a prepared list of questions that they can consistently ask each candidate. This may feel less interesting to the interviewer, but consistently asking the same questions will allow for an apples-to-apples comparison of the job seekers. It will also ensure that the candidate -- not the interviewer -- does the talking.

Related: The Secret to Closing More Sales: Talk Less

5. Not properly onboarding. Once Tom does find that perfect candidate, makes the offer and ultimately hires his newest A-player, he has no consistent onboarding process. Whereas Fortune 1000 companies have the resources to formally onboard new hires, many small and midsized companies don’t have a process that goes beyond arranging for a new hire to shadow an existing employee. Tom and his team need to spend some time formalizing the onboarding process: What training, mentoring, technical assistance and emotional support will the new employee receive? Many staffres end up with a sour taste in their mouths when it comes to their new organization if management hasn't arrived at clear answers to these questions, 

By addressing all five of these very common hiring mistakes, Tom (and you!) can finally develop that team of rock-star employees needed to catapult the firm to success.

Do you have a good strategy to hire A-players? Please share below in the comments.

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