There is no learning without mistakes. The essence of the double bias of mistakes is the contradiction between an often-declared positive attitude towards learning from mistakes, and negative experiences when mistakes occur. Financial and personal consequences, shame, and blame force desperate employees to hide their mistakes. These adverse outcomes are doubled in organizations by the common belief that managers never make mistakes, which makes the contradiction even more harmful. Double bias affected leaders select only easy tasks to secure their positions, and those who want to be promoted hide their mistakes to maintain the image of a “perfect employee”. Avoiding the risk of failure is generally not wrong as long as doing so does not block organizational growth. It has been proven that the double bias of mistakes can present a serious hurdle for organizational learning and collective intelligence building. This study explores whether the double bias of mistakes is gender-related and how it affects tacit and explicit knowledge sharing. To do so, it is based on a sample of 183 Polish knowledge workers affected by the double bias of mistakes. The analysis method was ordinary least squares regression, which was conducted with SPSS PROCESS software. Results show that the double bias of mistakes generally causes more problems for female specialists than male specialists and more for male managers than female managers. Regarding managers, male managers probably tend to focus more on control at work. In contrast, women focus on supporting learning (they accept mistakes as a source of knowledge and share knowledge gained from them). Considering current challenges relating to collective intelligence building, women seem to have the potential to be better mentors and probably also better leaders than men. Such formulated conclusions are based on indirect inferences, so further research is necessary.