"Project vision" is probably better. It's about what should developers focus on: Performance, deadlines, or readability/maintainability.

If software is expected to be in use for a long time (OS, business core app, etc), it's important to be durable and maintainable. Programs for one time use (data migration, for example) don't need to be maintainable. Code rot is not the problem here.

Sometimes, if you need planned obsolesence, code rot is even desireable. Customers might not like it, though.