All right, AndyPTG from Boston asks: „Will I be penalized for having every file in my XML Sitemap listed with the same priority? I get a warning about that. At the same time, the priority field is optional.“.
Well I definitely don't think you'll be penalized. If you give all of those files the same priority, then we'll just try to sort out which ones we think are the most important on our own.
So I definitely wouldn't worry about having to list a priority for every single one – it's not like we're going to have some scoring penalty or anything like that. It is totally fine and it's totally optional so, if you do have some information that you can use to put into a priority, that's great, but it's not required and it won't get you in trouble if you do or don't have it.