Soffit slopes toward house and acts as a gutter. This directs moisture into the wall system above the slider and has created a problem with the trim shown in images above. Exterior gyp wall sheathing not protected by a WRB (weather resistant barrier).
Gyp wall sheathing not protected by WRB and wall above garage roof.
Gyp wall sheathing not protected by WRB.
End unit FP Chases have a WRB. This does not appear to have been original but a repair at a later date.