Whether they're recruiting for a "purple squirrel," "unicorn" or "rock star," tech hiring managers say there is often a disconnect between the skills they need and the skills of the people they hire. In new research from Robert Half Technology, 95 percent of IT hiring decision makers admitted to making a bad hire, and 38 percent acknowledged it was due to a skills-based issue, meaning the new hire was unable to do the job as expected.

Interpersonal issues (29 percent) and poor corporate culture fit (28 percent) have also contributed to hiring mistakes, together accounting for over half of bad hires, according to IT leaders.

The challenges may start early on in the hiring process, as 39 percent of IT managers said adequate technical skills are the most difficult thing to evaluate during a job interview. Corporate culture wasn't far behind, at 37 percent, and 23 percent of survey respondents said soft skills are hardest to gauge.

View an infographic with the full results of interview issues and hiring mistakes.

"Hiring someone who is a poor job fit can hurt your business by hindering productivity and eroding team morale," said Ryan Sutton, district president, Robert Half Technology. "Current employees who are likely already stretched thin must scramble to fix mistakes or handle extra work."

Sutton continued, "The interview process should be thorough enough to evaluate technical and soft skills, and determine a candidate's fit with the organizational culture, while also being fast enough to avoid losing top prospects to other offers."

Robert Half Technology provides five tips to help hiring managers avoid costly mistakes when recruiting IT talent:

• Be clear with what you want. Recruiting the right talent starts with a solid job description. When drafting one for an existing position, re-assess the responsibilities to ensure the current requirements still match the role. If it's a new position, include the full scope of duties so there's no confusion once an employee starts.

• Test tech skills. Have strong candidates take a technical assessment to test them on key skills required for the role.

• Get your team involved. When conducting interviews, have peers, direct reports and other colleagues meet with the candidate early in the interview process. This will give you insights into the potential new hire's interpersonal skills and whether he or she will be a good fit with the team and your corporate culture.

• Be flexible. In this tight candidate market, it's challenging to find applicants who meet 100 percent of the requirements. Determine which skills and experience are must-haves versus nice-to-haves and be willing to train promising candidates who may fall short on skills or experience but would otherwise be a great fit.

• Take a trial run. Consider bringing on a contract employee when you're hiring for a critical role. This will take some stress off your team while allowing you to evaluate the candidate's fit for a full-time position.