The choice to focus on a journal's impact factor, or its quartile, in authoritative rankings, when deciding where to publish research results can be driven by various reasons. These may include personal prestige, enhancing the appeal of a CV, the desire to increase publication-related rewards, meeting the conditions of scientific funds, or fulfilling qualification requirements. While these considerations deviate from the pure science perspective, the fact is that they are widely adopted. Our research demonstrates that the conventional division into journal quartiles may privilege certain disciplinary categories while disadvantaging others. Disciplinary categories in Journal Citation Reports (JCR) and similar rankings are imbalanced in terms of the number of articles across different journal quartiles. This is attributable to three factors: the distribution of journals across quartiles, the varying volume of journals, and the selection of the highest quartile when journals are categorized under multiple disciplines. Narrower research areas, such as Topic Clusters from SciVal, may completely lack Q1 journals dedicated to them, or even any such journals at all. This finding might also interest publishers when selecting topics for launching new titles. The apparent inequality between disciplines unveiled in our study offers a new perspective to argue against the use of quartile metrics, at least in a straightforward manner, when evaluating performance and shaping science policies.