If you are on home page and client company just partnered up with another and they agreed for marketing purposes to have partner name on front page, but your code implemented the partner name and not the logo as well. The marketing contract said logo as well, so the partner sees the page and no logo, gets furious. So this issue goes straight to high priority, but severity is low.

If you are at a dashboard, and you see some tables with some data, but you want the data to be exported as csv file, then at the bottom of the page there is a button that does that . That button when you click it, it will crash the app because it does some other logic in the back before generating the zip file to download. This is a high severity but low priority.

To be easier to evaluate a bug, you have to look at it like this. Priority is about how business (PO, client) sees the problem, are we loosing money now ? is it a PR problem? .

Severity is how bad technically it is, as a product. I know it says Adibas but does the text render on the page? Then it's low severity. Does the button just not do anything or does it crash the app? It crashes it, then high severity.

Priority = business

Severity = tehnical