Work, how not to UX
I may have griped about this before, but this is still...what.
So this page at work has two fields that need filling. They're very simple formulas, X*Y. Y is a very small number and easy to typo.
The software will not fill these values for you, users are required to calculate and input manually. HOWEVER if you get them wrong it errors and refuses to save. So everything is being calculated just..ignored except to annoy me.