The enterprise or strategic vision for Splunk (as with most tools and technologies) is based on an evolutionary roadmap that evolves from the initial evaluation and implementation to building and using and finally (hopefully) the management and optimization of the tool or technology:
The evaluation and implementation phase will generally cover the discovery and evaluation that takes place with any new (to the organization) tool or technology. Testing should cover everything that is required to determine whether the tool/technology will meet or exceed the organization's needs now and in the foreseeable future. Once a decision is made to move forward, this phase also includes the installation, configuration, and everything that might be involved in deploying the new tool or technology for use by the intended users of the organization.
From a Splunk perspective, this phase might involve downloading and configuring an evaluation copy of Splunk...