Thank you for your question. In critical thinking the ‘why’ question is important to understand purpose, the reason for a piece of information. Do not confuse this with ‘why’ questions in the test(s). When you ask the former ‘why’ – purpose – it leads you to understand the EXPLANATION more clearly. When you practice identifying this purpose or explanation make sure you keep it simple. Many of the questions which follow the passage ask for these PURPOSE or EXPLANATION type information. Hope this helps.