One of the benefits for employers of using temp-to-hire placements is that you have the opportunity to observe the worker on the job before you make a longer-term hiring decision. If someone isn't a good fit in the position, you have no obligation to retain them. You don't even have to tell them you are not hiring them as that is the responsibility of the staffing agency.
1. Does the individual have the right basic skill set?
2. Is the individual interested in learning about your business?
3. Does the individual volunteer to take on additional responsibilities?
4. Does the individual fit your company culture?
Skills testing is typically completed prior to placement. However, observing an employee's performance on the job provides an excellent opportunity to determine the worker's aptitude and skills.
Asking questions about the business and volunteering for additional responsibilities are strong indicators that the employee very much wants to stay with your company for the longer term.
Perhaps, most important, does the employee fit your company culture? If the employee is comfortable communicating both on an informal and a formal basis with other employees, it is likely they will be the right fit for the position and for the company culture.