Manager's Responsibilities, Limits
The tenants and manager need to have a common understanding of the manager's duties and responsibilities. If a tenant thinks the manager can help them with home repairs, picking up groceries or sorting out their meds, there's definitely a disconnect. Likewise, tenants who think a manager can resolve a "beef" with their neighbor or somehow control a tenant who is "acting out" or even breaking the law will be frustrated and disappointed.
Success means the tenants know who to call when they have a home repair that needs to get resolve. When they need groceries or help with other personal chores, they get connected up with social or community services and perhaps someone who can run errands. Tenants know they need to get along with their neighbors and if there's an issue, they need to meet with them, discuss the issues and find a resolution. If there's a tenant who is not complying with the rules, they'll let the manager know and if the activity is threatening to them, their property or it's criminal, they will immediately call the police.
Provide the tenants a list of vendors who can do home repairs or run errands
If there is a tenant dispute, offer to host a meeting in a neuetral location and facilitate a discussion that might lead to a resolution of the isues
Periodically remind the tenants if they are ever threatened, fear for themselves or their property, they should immediately call the police