Confusion about move_base_simple and posestamped

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Whn using move_base_simple woth posestamped to set waypoints, I notice something. When I set posestamped frame_id to "map". when I set an x and y pose, lets just say x=1 and y=2. When I set the robot to go there, it reaches the goal on the map, but when I set the robot to move to exact same x,y position immediately after, it moves to a different part of the map. Not sure why this is.

As a sort of second question: self.listener.waitForTransform('map', 'base_footprint', rospy.Time(0), rospy.Duration(0.5)) waits for a transform from map frame to base_footprint frame? Or vice versa?