Increasing market share is one of the most frequently cited business objectives, as it is assumed that more market share also leads to higher profitability. On the one hand, our study theoretically examines this relationship, which has changed due to globalization and the digitization of the economy; on the other hand, we carry out an empirical meta-analysis in which we evaluate almost 90 studies on the relationship between market share and profitability over 45 years - covering all relevant industries and continents. Based on over 800 identified effects, we find that financial performance only increases by an average of 0.13 percent if market share increases by one percent. This result is surprisingly low and above all significantly lower than the influence of customer relationships (six times stronger) and brands (three times stronger). We also find that the relationship between market share and profitability is highly context dependent (e.g. by region, industry, market maturity). Companies should therefore question the focus on market share as a key performance indicator (KPI) and adjust its use as a strategic metric in a differentiated manner depending on the specific conditions the company is facing.