The ADA requires employers to make reasonable accommodations for disabled workers. That can mean modifying the employee’s existing job so he or she can perform the essential functions. But disabilities can change over time, and an accommodation that’s worked for years may stop working. If that’s the case, the disabled employee and his employer are both obligated to engage in another interactive accommodations process. However, if the discussions reveal that no amount of accommodation will allow the employee to do the job satisfactorily, it’s time to look for other solutions …