You are a team leader of one software project. Your team has just completed an important project. When the project has been deployed and tested into the intent environment, the customer identified a major defects in the system. The system needs to be fixed immediately. However, when it comes to fixing the defects, each of your team members are keep blaming each other.

Analyze the root cause of the issue. As the team leader, suggest FOUR (4) solutions that you would address to avoid your team from doing the same mistake in the future.