WHY A JOB WILL NEVER KEEP YOU MOTIVATED
In the beginning, you need a job. When you are hired, you and the job become one. Soon you believe the job cannot do without you. When you've been fired, or retired, you realize that you are not the job. The job can go on without you. When you leave, you discover that the job and you were never one.
There is much debate about how employers should motivate employees to work. This is only true if employers believe that employees and the job are one. If they are not one, then what attracted employees to the job should sustain them through it. This means that it is the employee's job to keep (themselves) motivated. If the two were never one, then the only way an employer can motivate an employee is to give them more work to do.
Jobs do not have motives. Only people do. Your motives change on the job in line with your needs in life. When this happens, you need to be very clear about what you ought to do, and what your employer will never be able to do. When a job no longer motivates you, check your motives, they might have changed.