It is quite natural for people to generally be committed when they agree with the plan or task. The bigger challenge for a manager is how to generate same level of commitment when employee or team doesn't necessarily see the wisdom in chosen path. Yes, you may involve your team in action planning, you could be extremely transparent etc......
The reality is that, in life and the workplace there will still be situations when you are asking people to do something, they don't want to do or when they disagree with the approach. This is when leadership skills come into play. From my experience, if I had to pick one leadership trait/characteristic to deal with this issue, it will be trust. If you completely (as complete as you can have at work) trust the person in charge, your commitment level will be considerably higher regardless the situation. Trust takes a long time to build and can unfortunately be easily damaged.
Listed below are three things that well earn and keep the trust of your people. What are they for you?
From past actions, I have no doubt that the person has my best interest in mind