> a) Almost every startup I know of that failed, failed because of business reasons, not tech. Even when it was tech, the reasons were delays in feature delivery and production issues, not code maintainability or tech debt. Some companies paid dearly later on to fix tech debt, but if they hadn't moved fast in the first place, they wouldn't have had customers to lose.

Delays in feature delivery and production issues are usually symptoms of poor code maintainability and high tech debt. It's a really difficult balance to strike, but it's worth tackling low-hanging fruit as you work on the code, and introduce good practices for new features as you keep going if it doesn't impair development too much.