Penetration often refers to the act of piercing or entering into a material or structure. In the context of this study, penetration refers to the most time efficient path of a crack, which is through the line of symmetry. This path is detrimental to the structure of a material, as it indicates the worst possible scenario of failure when the crack is propagating through a material . Unlike deflection, penetration can be an undesirable property in certain materials or structures, as it can lead to critical failure. When faced with the decision of penetration vs. deflection, it would be wise to select deflection in most cases, as the material can often save time until failure and can even be render trivial at the macro-scale versus an immediate penetration case .