Ask HN: How can I consistently deliver high-quality work with minimal issues?

TL;DR: What are your checklists, tips, and tricks to ensure you're delivering a high-quality piece of work (whether it's a Pull Request or something equivalent in your field)?

As a full-stack developer, I've often found myself in situations where a sprint goes wrong, and a lot of bugs are flagged by QA. It's a tough spot to be in because I genuinely put in my best effort when coding, but sometimes things just don't go as planned. It could be due to a new feature, an old legacy system, or simply a rough week—it happens from time to time (not so often, I remember like 4 moments in my 5 years of experience). What advice do you have for maintaining consistent deliveries with minimal bugs (or equivalent failures in your area)?