To expand on something you hinted at. I think it's a very important insight to realize that your code base doesn't have to be homogenous, and you can make different trade offs in different parts of the app.
If you have an accounting app for instance, if it crashes every once in a while users will accept that. If it calculates your taxes incorrectly leading to an IRS audit, that is unacceptable and an existential threat to your company.
In that scenario UI could be messy but your tax crunching code has to be the cleanest and best tested code you can write.
If you have an accounting app for instance, if it crashes every once in a while users will accept that. If it calculates your taxes incorrectly leading to an IRS audit, that is unacceptable and an existential threat to your company.
In that scenario UI could be messy but your tax crunching code has to be the cleanest and best tested code you can write.