And even for purely UI changes, the UI totally impacts user adoption. Eg, a 90s style grey everything form is going to feel outdated to many users and they’ll associate that with the rest of the software being dated (regardless of whether or not it’s true). If your goal is adoption/sales, you often have to keep changing the UI even if it’s not broke with regards to functionality.
And even for purely UI changes, the UI totally impacts user adoption. Eg, a 90s style grey everything form is going to feel outdated to many users and they’ll associate that with the rest of the software being dated (regardless of whether or not it’s true). If your goal is adoption/sales, you often have to keep changing the UI even if it’s not broke with regards to functionality.