You might assume that job descriptions are only for advertising available positions. However, you can use these documents to outline duties for employees who are already hired. Job descriptions are also useful tools for performance appraisals. Summarize a job -- including its responsibilities, qualifications, salary and benefits -- before determining success metrics. Your metrics may be quantitative or qualitative, as long as they yield measurable benchmarks for employee success.

Functional Performance

Monitoring how well an employee performs his job is essential to maintaining a competitive business. Choose success metrics that reflect work processes for an employee to get the job done. In some cases, like a toll booth collector, very few functional tasks are required. Other jobs, such as construction engineer, demand a greater numbers of tasks. No matter the number of functional tasks, an employee’s effort levels or skills may vary. An example of a functional performance success metric is: “Employee completes design of all buildings listed in the work account according to all specifications.”

Revenue and Profits

Create success metrics that reflect the revenue and profits your employee generates. While you could argue that all employees’ work affects your company’s bottom line, focus on dollars that are generated from an individual’s performance. It’s common for positions that directly affect revenue and profits to have commissions or bonuses tied to them. A sample metric for a sporting goods clerk is “to meet a weekly quota of selling at least $500 in merchandise.” Another example is for a law partner “to expand the firm’s existing client base by at least 10 percent each quarter.”

Time-Based Performance

Stipulate success metrics that are time-specific. Choose measures that require detailed changes in performance over time. For instance, require a baker “to produce 20 commercial cookie sheets per hour.” Alternatively, a time-measurable success metric for a machine center operator is “to reduce his scrap rate by 5 percent over a three-month period.” Ultimately, success metrics that adhere to time limits encourage efficiency and reliability in your employee.

Employee Growth

An often ignored yet essential area to measure job success is employee growth. An employee who grows is not only more empowered, she is also more productive -- translating into greater gains for your company. Set metrics that challenge your employee from the outset, encouraging her to reach towards peak performance. Possibilities range from having her take on more responsibility for her work -- such as planning or coordinating her own schedule -- to developing an entirely new line of products or services.