For a first GTM hire, prioritize: process-building ability (can they design a workflow from scratch?), data fluency (can they build and read pipeline reports?), cross-functional communication (can they work with both technical and non-technical stakeholders?), and CRM proficiency (are they genuinely hands-on in Salesforce or HubSpot?). Revenue-generating track record matters, but cultural fit and adaptability matter more at the first hire stage.