Without aiming to ‘rehabilitate’ the Special Theory of Relativity (SRT), which would be a useless scope, we point out some inadmissible misinterpretations and misunderstandings of its basic reasoning methods, which we found in many papers or web sites. In more detail, it is not well understood that relative velocities are measured from a referential frame, and their values depend on the frame from where they are measured. Therefore, some authors do not fully understand the Einstein’s original second postulate of SRT, which stipulates the velocity of light is a universal constant. As a consequence, they reject the Lorentz transformations, the length contraction, the time dilation, as well as other consequences of the special relativity. In this study, we intend to somehow stop this kind of ‘perpetuum mobile’-type intentions, as well as this process of naïve criticism of SRT, which unfortunately is gaining an increasing number of adepts. We hope this paper will help learning and teaching relativity.