Edit: it appears that this is not exclusive to ADHD.
Posting this meme stemmed from my own efforts to explain my thought process when doing math and how it is similar to other people with ADHD doing math, while being different from every neurotypical person I'd talked to on the same subject.
While I didn't make the meme itself, instead finding it in my saves and wanting to share, I did accidentally spread misinformation that I had only backed up with personal anecdotal evidence.
I'll leave this up just so people can see the explanation below but this appears to not be ADHD related and just due to different people doing math in their heads differently...
Dude trying to get it from first principles!
Which is what I also lean towards. Give it to me step by step and I need to clearly map out each one... then the mind wanders and when I snap back to attention, I've lost the plot already, my mathematical surroundings are unclear, disorienting.
Add to this an erratic series of math teachers - some of them good, some of them blah - and this day trigonometry to me is a jumbled mess, but I loved calculus and was pretty good at probability and statistics.