Frequently, devs over-engineer to flex design pattern knowledge or anticipate extensions that never come. Distinguish between problems that need sophisticated solutions and problems that need simple ones.
If a single class handles the job without getting messy, don’t split it up. If it grows to 500 lines with 10 different responsibilities, then refactor.
If you can solve the problem with a simple conditional, use that. If adding a
new payment method means modifying code in five places, then introduce a
Strategy pattern. But start simple.
- Design Principles | Hello Interview Low Level Design. www.hellointerview.com . Accessed Sep 10, 2026.