There is an additional step of list-tasks, followed by scrolling through the tasks to find the exact task to unassign from the person. This can be very inconvenient and take a long time when there are a lot of tasks created. Since only tasks currently assigned to the person can be removed, the user should be able to only look at the person's task list when unassigning tasks. This is not much harder to implement and would be much more convenient to the user.

There is an additional step of

list-tasks, followed by scrolling through the tasks to find the exact task to unassign from the person. This can be very inconvenient and take a long time when there are a lot of tasks created. Since only tasks currently assigned to the person can be removed, the user should be able to only look at the person's task list when unassigning tasks. This is not much harder to implement and would be much more convenient to the user.