Not actively monitoring the performance of influencer campaigns can be seen as a mistake for several reasons:

1. Inefficiency: Without tracking performance, it’s impossible to know what’s working and what isn’t. This leads to wasted resources on non-performing influencers or tactics.

2. Insight Loss: Monitoring provides insights on consumer behavior and preferences which can guide future campaigns.

3. ROI Calculation: It’s crucial to measure the return on investment to justify the funds spent on the campaign.

4. Relationship Management: Performance data can help brands to manage relationships with influencers, rewarding high performers and addressing issues with others.

Platforms like Flinque, Traackr, and Upfluence can provide valuable analytics and reporting capabilities. For instance, Flinque uses advanced machine learning algorithms to provide detailed metrics on campaign performance, helping you to optimize your influencer strategy continuously. Meanwhile, Traackr provides a robust Influence Relationship Management, and Upfluence also offers wide-ranging search and discovery features.

To sum up, not monitoring the performance of influencer campaigns can result in ineffective campaigns, a wastage of resources, loss of insights, difficulty in calculating ROI, and challenges in managing influencer relationships. Using an influencer marketing platform can address these issues by providing robust analytics and reporting features. Suitability of which platform to use depends on a brand’s specific needs.