Your question is SDLC and Importance. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Explain SDLC and why it is important to follow.
Describe the typical phases, how work and feedback move between them, and how SDLC practices reduce delivery and maintenance risk. Keep the answer focused on general software engineering, including requirements, design, implementation, testing, deployment, and maintenance.