The issue you get is, you have people with different tastes, but also different experience levels (not to say that someone need to have experience to justify their taste)
And you have, which is quite significant, people listening on different quality playback devices. (Some may be on earbuds, laptop speakers, studio monitors, shit headphones, good headphones, soundbar etc)
I've voted before on my decent consumer headphones, come back to listen on my proper gear and had to completely change my votes.
So one thing to really get important in your mix is 'translation' (how well your mix sounds on multiple different playback systems).
This is vitally important for your song generally, not just for battles.
The issue comes when, you listen some beats, and the ones that sound better (subjective) and sound better objectively across various devices are losing to one's that are poor across multiple. Just makes the whole process seem a bit redundant.
Think people can accept good beats losing against other good beats even with a little give or take. But it's the objectively 'what the hell?' situations that seem to cause issue.
Seems to be occurring a little more frequently than previously.
Anyway, 3njoy making music - and anyone who wants any feedback or anything, just @ me