The free ELK stack, comprising Elasticsearch, Logstash, and Kibana, may appear cost-effective but incurs significant hidden expenses when self-managed, particularly for mid-sized companies with substantial data needs. The Weber-Fechner law illustrates how users perceive these costs as lower when integrated into existing expenses, yet maintaining an ELK stack on AWS can total approximately $2,416 monthly, factoring in hardware and personnel costs. In contrast, AWS Managed Elasticsearch Service reduces setup and maintenance time, resulting in a monthly cost of about $1,606. Despite the allure of a self-managed setup, fully managed services that offer additional features such as higher availability, redundancy, auto-scaling, and machine learning capabilities often provide better value, as evidenced by Coralogix's machine learning-powered log management solution, which supports the ELK experience while minimizing maintenance hassles.