Mortar and caulk is needed to properly seal the exterior of this home from moisture, wood destroying organisms / insects and air infiltration. As can be seen on this New Home Warranty Inspection in Cibolo  the home needs attention with corrections in numerous areas. All dissimilar materials should be caulked / sealed. In the photo above, the masonry meeting the soffit area of the cornice needs to have the mortar touched up along with proper sealing at the joint of dissimilar materials with an adequate exterior caulk.
  
In the photo to the left the masonry, from below meeting the siding should be caulked to seal it . Also the loose nails and siding , as shown should be properly fastened. The photo to the right shows more masonry on this home that needs to be properly sealed with mortar and caulk. The masonry shown in the photo should be properly sealed with caulking to disimilar materials, as in this case the cornice materials.
The photo below shows excessive openings in the garage door area attributed to improper installations. The garage door jamb is cut too short and is not sealed/painted on the bottom edge. Weatherstripping on the side between jamb and door is cut short along with the weaterstripping on the bottom of the door not sealing to the slab. All this creates a large gap for ................

Photos by JWK Inspections, San Antonio Home Inspector