The document discusses troubleshooting techniques for issues with DEEP: Data, End-User, Environment, and Product. It provides examples for each category to consider when troubleshooting an issue. These include checking for corrupt data, how the end-user is using the product versus how it is intended, ensuring the environment meets requirements, and identifying limitations or defects within the product. The document emphasizes starting with Data, then End-User, Environment, and Product, but also notes there may be times when skipping around is necessary. It stresses doing due diligence, having a plan for next steps, and making the client feel confident in the troubleshooting abilities.