Eyebright
Eyebright is tiny. It’s one of the smallest, low-growing plants that it’s possible to see and recognise while walking. To photograph it you have to lie on the ground and even then you’re not low enough.
The purple lines and yellow markings are very distinctive, but they’re tricky to see with the naked eye.

I’m told it’s very difficult to identify to species, because there are twenty of them, together with sixty hybrids.
I’m not even going to try. Do you judge me because of that?