Keeping your employees motivated is not only important for the overall atmosphere in your company, but also when it comes to their productivity. You want them to feel integrated in the process and not feeling like just another brick in the wall. They need to believe in your company's vision and constantly give their best effort day in and day out.
This is probably easier said than done, but there is a way. The first part of the process is letting them know how important they are for the big picture of your company and that they are a valuable piece of the equation. Since motivation needs to be fostered on a regular basis, you will have to communicate with them frequently if you want to have long-lasting results.
Ask them what they are struggling with and see if you can be of any help. By knowing what's bothering them, you will have a better chance of remedying it, thus lifting their spirits and increasing productivity and motivation.
The second step is making sure to always have an open discussion about problems. After all, that's what business is all about - solving problems! And if you're working in a company that does everything to make the quality of people's lives better, that should be a strong motivator all by itself. But you have to make sure your employees are on the same page, otherwise this is not going to work.
You should also invite them to speak about their ideas openly. Fresh ideas are the driving force behind innovation, and that's something every reputable company should be striving for. If your employees get a chance to contribute their thought process and ideas, they will naturally feel like they belong to the team and that their say has a certain value. This is a win-win situation; you will get a whole list of new things to try out, and your employees will feel more than happy to share their thoughts with you.
Finally, you should do your best to explain the purpose behind every task you're handing to your employees. If they don't know what the overall picture should look like, they will struggle to produce something that matches your criteria. But if you choose to invest a little bit of extra time to explain what you're trying to do, they will be more inclined to put their creative juices to work and deliver outstanding results.