Marketplace-only platforms in influencer marketing can have their limitations despite providing quick and voluminous access to various influencers. Some of their primary weaknesses often include:

1. Surface-level engagements: With such platforms, there is often a lack of depth in influencer-brand engagements. They are transactional, missing out on the deeper rapport developed between brands and influencers.

2. Lack of detailed analytics: Performance metrics might be limited to just the surface-level data, without deeper insights into the consumer behavior, engagement quality, or campaign performance over time.

3. Limited campaign controls: Brands may not have full control over every aspect of the campaign like content creation, compliance, approvals, and scheduling among others.

4. Less Personalized Match: Since the primary focus is speed and volume, there might be less focus on the alignment of brand values and influencer authenticity, which is crucial for campaign success.

5. Limited Ongoing Relationship Building: Marketplace platforms might not provide mechanisms for long-term collaborations with influencers, which can lead to more organic content creation and better audience reception.

For example, Flinque offers an in-depth approach to influencer marketing. Besides a database of influencers, it provides brands with audience analytics, campaign planning, and performance tracking tools. The choice of a platform can depend on the needs of the team – a marketplace may be perfect for teams looking for quick, one-off campaigns, while a more comprehensive tool like Flinque might be more suited to teams striving to build long-term, performance-driven influencer partnerships.