Every person is motivated by something and it is up to you and your company to determine what that is. It's either internal or external, internal or external. Some people want to do a "good job" because they are wired that way and others want and crave recognition from others, so they want an actual reward, like "Leasing Professional of the Month" plaque. I think when there is a great deal of turnover, it will end up being due to salary/commission structure, hours worked (too many, too long a day, or every weekend), lack of recognition, feeling like their efforts are not getting them ahead (promoted) or there is too much stress on an unattainable leasing goal. For example, if you told me I had to lease 12 apartments in a month on an 87-unit property I would look at you and walk out the door. If you told me the team needed to lease 12 apartments, then that competitive gleam might get ignited, plus it would not be left to me to achieve the total alone.
I always have it be a team goal based on intents, etc., but also on what kind of leasing success should be achievable on the property. Older products with no amenities are much more challenging when the comp a block away has a newer product with tons of amenities. I also have a team meeting and work on ways to achieve the goal. Again, some people can't think on their feet as well as others or lack confidence in a group setting.
Next, look at the total picture. Are the leasing and maintenance teams working well together? If so, are they working well with you as a manager? Make sure no one feels neglected - is there one leasing person demanding all of your attention, or are you always on the phone or in a meeting with corporate? If these are working well on all fronts, I would then be asking your team for their input into the issues. I still bet it is pay, hours worked, and stress.
Make sure your leasing team has the tools it needs to achieve goals and be happy. Bring in pizza once a month, let everyone go home early with pay - have the manager take a Saturday rotation. Take your leasing team on tours of other properties, stop for lunch and give everyone $25 to set up a mini model or use the $25 for outreach marketing - get everyone's creative juices flowing. This breeds excitement, too. Sometimes just writing team members notes of appreciation helps make them feel a part of the team, too.