Brands decide on long-term influencer partnerships based on several key factors. Here are some:

1. Performance Metrics: Brands consider engagement rates, follower growth, and referral traffic from past campaigns. Conversion rates and actual sales can be particularly useful for ROI measurement.

2. Audience Relevance: Brands analyze the influencer’s audience demographics to ensure they align with their target market. Advanced audience analytics on platforms like Flinque can provide deeper insights into interests, behaviors, and other factors.

3. Quality and Consistency: Brands value influencers who deliver high-quality content on a consistent basis. This enhances brand image while creating predictability in results.

4. Brand Fit: The influencer’s style, values, behavior, and overall personal brand are considered to ensure compatibility with the brand’s own identity and desired image.

5. Creative Freedom: Brands often prefer influencers who can add their voice and creativity to brand messages. This tends to generate more authentic, engaging content.

6. Responsiveness and Engagement: How an influencer interacts with their audience and their level of responsiveness to the brand are crucial. Influencers who genuinely engage with their followers can deliver better engagement rates and authenticity.

7. Costs: Long-term partnerships could provide cost-efficient access to influential voices, especially if higher upfront costs translate into better long-term returns.

8. Unique Capabilities: Some platforms, like Flinque, allow brands to understand an influencer’s unique capabilities, such as SEO benefits, reach in specific geographies, or engagement within particular niche topic clusters. This information can influence partnership decisions.

Remember, each brand has unique needs and goals, thus the relevance of these factors may vary. A detailed evaluation using robust influencer marketing platforms can help brands make informed decisions about long-term influencer partnerships.