That's very true, many of the WCAG success criteria are subjective. Some criteria are pretty cut and dry, like needing to meet a 4.5:1 color contrast ratio for text, but others can be a little more open, like how to provide keyboard navigation for complex widgets.

It sounds like you're asking for advice on how to push back when you're on the receiving end of an accessibility audit, maybe with some findings that you don't agree with.

I'm not sure if this helps for your specific situation, but some pointers that I've found useful are:

1. You'll often get different findings from each audit. People are imperfect, and they miss things. You might have someone audit the same page twice and find different things each time.

2. Try to fix what you can. If you're in doubt on the validity of a specific report item, you can always get a second opinion.

3. For subjective criteria, it's helpful to look at recommended patterns. I'd highly recommend checking out the WAI ARIA Authoring Practices guide for how to implement complex widgets and patterns.

(https://www.w3.org/WAI/ARIA/apg/)

4. When pushing back on feedback or prioritizing what to fix need, it's helpful to think about the feedback in terms of importance. I often rank my feedback on a scale of P1-P4 (priority 1-4). You can come up with your own definitions, but often it's something like:

P1: Blocker. A user with a certain disability can't use this feature at all.

P2: Partial blocker. A user with a certain disability can use this feature, but it's very difficult or unintuitive.

P3: Minor improvement. A user with a certain disability can use this feature, but there are some small improvements that could be made, such as improving a slight color contrast violation or adding a helpful aria attribute.

P4: Best practice, but not required. The feature is usable, but we could implement it differently to provide an even better user experience. This often means adding additional functionality rather than just fixing existing content.

That was a smattering of advice, but hopefully at least some of that was useful to you!