Stability analyses of slopes have been a hot topic for several decades and numerous methodologies have been introduced since the beginning of these analyses. One of these methodologies is the limit equilibrium theory, and it has been applied in different forms to various cases for almost a hundred years. Although numerous investigations and works have been carried out on this methodology, there are still wide gaps needed to be investigated. Various methods have been introduced through the years including two- and three-dimensional solutions to the slope stability. However, an extensive investigation on the effects of real-life scenarios is still absent in the literature. Therefore, this study was aimed at modelling and evaluating the slope stability considering different scenarios in two (2D) and three dimensions (3D). Available methods have been investigated in both 2D and 3D separately by considering well known cases in the literature. Also, a comparison has been conducted between two- and three-dimensional versions of the same methods. Five different hypothetical cases and a multitude of scenarios representing the possible conditional changes on the slopes were investigated during the analyses. Thus, three distinctive comparisons have been conducted by analyzing 942 data related to the factor of safety. Many intriguing results have been discovered throughout the analyses and some of them have been found against the literature. A considerable amount of the computations has produced lower factors of safety in three-dimensional models. This outcome is arguably the most significant finding of this study.