Some people cannot be convinced of this, but some can, as long as you don't use technical language to describe the issue. Essentially, instead of saying "we need to prevent technical debt and have a maintainable software architecture" one needs to say stuff like "software quality enables a faster time-to-market for new features and less customer churn". i.e. put it in business-y terms.
Yes, but then it's really important to demonstrate that this is true. If they invest in what you propose, time to market for new features needs to actually become faster, or customer churn needs to actually decrease. It's not enough to put the proposal in business-y terms, it has to actually effect the claimed improvements to the business.
