Assessments aren't just another step in the hiring process anymore, they provide a neutral way to screen candidates based on their workplace fitness. They're inexpensive to find, results can be accrued in minutes, and considering the leaps and bounds made in psychology over the last several decades, they are typically more accurate than the initial judgement that comes from face to face interviews. That accuracy is imperative because hiring is expensive and, consequently better hiring leads to higher employee engagement and smaller turnover. Assessments alleviate many of these unknowns and provide more accurate analysis.
It's not uncommon to hear people say "I don't interview well" and vice versa but that doesn't make their skills any more or less valuable. Face-to-face interviews are often inconsistent and a good interview, for a normal candidate, depends on a variety of factors beginning with their commute to the company office and ending with whether or not the employer was having a notably bad day. These little things can severely impact perceptions of the candidate and the employer.
Make sure your assessment is tailored to the specific needs of the company or the particular positions that need to be filled. Look at the competencies needed in specific positions or even just to assimilate to workplace culture and make sure you are asking questions that help get the biggest, most accurate picture of an applicant before you interview. If you have an idea of who is going to walk through the hiring manager's door, you can tailor interview questions based on the assessment so you and the candidate can have the most productive interview possible.
That being said, no employers should rely completely on the results without looking over them thoroughly. While they're most accurate assuming that a 90% means a great fit every time - the ten percent that's missing could be critical. It's not impossible that a candidate might pass every section with flying colors but one section about introversion could make them a miserable fit for your sales team. On the opposite end of the spectrum, strong organizational skills could make another candidate a fantastic member of your event planning team.
These assessments can be extended beyond hiring and applied to other elements of the employee's work life. Workplaces that use pre-hire assessments that ask questions about employee engagement often have more engaged employees than their peers. These pre-hire assessments can also provide a baseline when it comes to evaluating employee performance and development. If an employee ranks themselves highly on a certain set of skills, it is reasonable to think that they will continue to perform those skills at a high level. The pre-hire assessment can help identify performance issues or areas of improvement when it comes time for employee performance reviews.