This study conducted an empirical analysis of 44 new ventures established after 1975 that rapidly grew into one of the representative top 500 U.S. companies within 30 years, demonstrating that their management performance is closely related to strategic actions such as diversification, mergers and acquisitions, strategic alliances, and niche market penetration. Additionally, the study sought to determine which factor—the firm effect, measuring company-specific competitiveness, or the exogenous industry effect—has a greater influence on the success of new ventures as major factors simultaneously affecting firm performance alongside the aforementioned strategic actions. Panel fixed-effects analysis results showed that new ventures achieved statistically significant higher stock returns through strategic actions compared to their initial competitors, with the effects ranked in the following order: niche market penetration, unrelated diversification, competitor-eliminating M&A, technology and labor force acquisition M&A, marketing alliances, and product development alliances. Furthermore, company-specific competitiveness linked to strategic actions, rather than industry effects, had a greater influence on the rapid growth of new ventures.