Sometimes, your employees can be stubborn. They would rather not let themselves be motivated by either their peers or their superiors. But that does not you should give up that easily.
Instead of trying to motivate your people, try creating a motivating workplace instead. Check out what your workers find motivating and infuse them in the office. However, do note that different employees have different motivations.
Ask your employees what they enjoy in every day. Determine what values and needs keep them motivated. It is best to conduct this employee survey annually so you have an idea make motivates, as well as demotivates, your employees.
You can also organize focus group discussions involving a small group of staff members and ask them what they think should be included in the workplace to keep them motivated. Another method is to talk to employees on a daily basis. Either way, it is all in the interest of keeping your employees happy and continue to perform at an optimum level.