The additional costs that arise due to wellbore instability problems in the oil industry have captured the attention of petroleum companies. At the beginning of the oil industry, most of the drilling activities were guided by simple geological and geomechanical models that were more than enough for the complication of the fields that were being developed. Nevertheless, in the last years, the implementation of directional and horizontal drilling techniques has demanded our industry to build more complex and robust geomechanical models to better understand the rock’s mechanical properties and behavior after drilling operations. The aim of this work is first to highlight the importance of appropriate geomechanical knowledge to prevent wellbore stability problems, mainly present in anisotropic rocks in the way of wellbore enlargements, to then recognize different breakout patterns around the wellbore vicinity.