When working with amcl why does the robot try to move closer to the wall in an open area rather than navigating more towards the goal?

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For example, the following

The robot is closer to the wall instead of following the path to the goal (green line).

I have noticed that happen all the time. Why is that so? Is there a particular parameter that influences this? As soon as the robot gets close to the wall it gets better at navigating straight to the goal I think. Or is it something related to amcl algorithm(s)?

Here is the robot shortly after reaching close to wall and then moving towards the goal again.

What causes such a pattern/behavior?

Update Based on Comment:

Here are some of the config/params I am working with.

move_base node

<node pkg="move_base" type="move_base" respawn="false" name="move_base" output="screen">
    <rosparam file="$(find robot)/config/costmap_common_params.yaml" command="load" ns="global_costmap" />
    <rosparam file="$(find robot)/config/costmap_common_params.yaml" command="load" ns="local_costmap" />
    <rosparam file="$(find robot)/config/local_costmap_params.yaml" command="load" />
    <rosparam file="$(find robot)/config/global_costmap_params.yaml" command="load" />
    <rosparam file="$(find robot)/config/base_local_planner_params.yaml" command="load" />

    <param name="controller_frequency" value="10.0"/>
    <param name="planner_frequency" value="10.0"/>

    <remap from="cmd_vel" to="cmd_vel"/>
    <remap from="odom" to="odom"/>
    <remap from="scan" to="robot/laser/scan"/>   
</node>

costmap_common_params.yaml

map_type: costmap

origin_z: 0.0 
z_resolution: 1
z_voxels: 2


obstacle_range: 2.5 
raytrace_range: 3.0 

publish_voxel_map: false
transform_tolerance: 0.5 
meter_scoring: true

robot_radius: 0.3 
inflation_radius: .6

observation_sources: laser_scan_sensor

laser_scan_sensor: {sensor_frame: hokuyo, data_type: LaserScan, topic: /robot/laser/scan, marking: true, clearing: true}

global_costmap_params.yaml

global_costmap:
   global_frame: map 
   robot_base_frame: chassis
   update_frequency: 10.0
   publish_frequency: 5.0 
   width: 40.0
   height: 40.0
   resolution: 0.05
   origin_x: -20.0
   origin_y: -20.0
   static_map: true
   rolling_window: false

local_costmap_params.yaml

local_costmap:
   global_frame: map 
   robot_base_frame: chassis
   update_frequency: 10.0
   publish_frequency: 5.0 
   width: 10.0
   height: 10.0
   resolution: 0.05
   static_map: false
   rolling_window: true

base_local_planner_params.yaml

 TrajectoryPlannerROS:
  max_vel_x: 0.5 
  min_vel_x: 0.1 

  max_vel_theta: 1.5 
  min_in_place_vel_theta: 0.314

  acc_lim_theta: 20.0
  acc_lim_x: 10.0
  acc_lim_y: 5.0 


  holonomic_robot: false