You can download the Gartner Hype Cycle for IT Infrastructure Availability and Performance Management 2015 using this this link
Regarding Capacity Management you can read
Users should invest in capacity-planning and management tools to lower costs, to more accurately forecast investment needs and to manage the risks associated with performance degradation and capacity shortfalls.
All business-critical IT services benefit from the use of capacity-planning and management tools to ensure high performance and minimize the costs associated with "just in case" capacity headroom excesses. These tools become essential when accurate infrastructure investment plans and forecasts are required.