Using a quantile regression methodology, this paper presents an explorative analysis of the factors driving route traffic and examines the heterogeneity of factors that affect route flight frequency. The results indicate that factors related to airline operations indeed exhibit a heterogeneous effect on various markets. Notably, the factor effects of having low-cost carriers (LCCs) in operation and the rate of codeshare flights showed a descending effect as the quantiles increase. This finding implies that routes in the low quantiles may represent an under-cultivated market, the potential of which is not yet fully exploited. On the other hand, routes in the upper quantiles represent markets that are fully exploited and tend to be mature. Thus, the under-cultivated markets are a supply-driven niche. As a consequence, LCCs and codeshare flights can boost and enhance the potential of the market. Compared to enhancing factors, route distance showed a relatively larger elasticity of impedance in fully exploited markets. This study highlights the heterogeneous effect of the affecting factors on route frequency. The findings provide very insightful information for airlines, airport operators, and policy-makers in developing their business strategies for various route markets.