When resource constrained organizations grow quickly, their leaders face the choice of balancing short-term organizational survival with long-term mission focus. If leaders are unable to quickly socialize their recruits, bottom-up internal pressures can transform the priorities and operational focus of the organization. In this way, an influx of recruits can simultaneously boost group strength and resilience while undermining the leader’s perception of success. This paper outlines the bottom-up transformation theory and illustrates the logic and outcome via the example of al-Qaeda in the Arabian Peninsula (AQAP). Methodologically, the paper combines primary source jihadi strategy documents and qualitative reporting with machine learning and text analysis to conclude that changes in AQAP’s activity patterns and self-presentation suggest that rapid introduction of personnel may have come at the cost of fundamentally transforming the character of the Yemeni-based militant organization.