Addressing consistently low-quality code requires a supportive and constructive approach. I'd start with a private conversation, focusing on specific examples and avoiding blame. I'd offer mentorship and resources, such as code style guides or training materials. Emphasizing the importance of code quality for maintainability and team velocity is key. If the issue persists, involving a senior team member or manager might be necessary to provide further guidance and support.

To address consistently low-quality code, start with a private, constructive conversation to understand the team member’s challenges and perspective. Provide specific examples of low-quality code and explain its impact on maintainability and team efficiency. Offer mentorship, resources, and guidance, such as code style guides, training materials, or pairing with a senior developer. Encourage participation in code reviews, both for giving and receiving feedback, and suggest using tools like unit tests to cover edge cases. Set clear expectations for code quality and provide continuous support, including assigning a mentor for ongoing guidance. Ensure that the focus is on improvement and create an environment of collaboration and learning.

Contribution to others success is one of the major pillers of employee's success and addressing the low-quality code issues in the team is a must. Senior engineers should setup KT sessions around best practices to enlighten everyone. It not only helps in individual growth but team efficiancy also.

Address the issue privately and constructively. Begin by discussing their challenges and understanding their perspective. Provide specific examples of low-quality code and explain its impact. Offer guidance, resources, or mentorship to improve their skills. Set clear expectations for code quality and encourage collaboration through code reviews, pair programming, or training sessions.

I would also like to add some specific scenarios:- 1. If SDE knows he is working on legacy code base then mostly the implementation pattern might already be defined when that codebase was created. So he can make a note of mistakes he does frequently because these mistakes will be limited and notes of these will help him to not repeat those. 2. If SDE is implementing a design doc feature in code, he should write down unhappy cases at each step of user flow by asking what can go wrong in design doc approach. So that when he will start implementing he will have all happy and unhappy cases and will not need to go back and forth while implementing. 3. Writing good unit cases is nice way to cover all edge cases. 4. BO, etc. come in lld not CRs.