Actually I have had lots of infections under the tag (probably a small tear), and not even soon after putting the tags in but months later... So I have been cutting the tags out and taken photos of the ear all oozing gunk etc etc. Then ordered replacements, but so far these live in a box...
None of the goats have torn their ears (YET), and for the sheep - none of the ones that I tagged (with SETtags from Shearwell) have so far lost their tags...

, but most of the tags of bought-in animals are half broken or lost... Have a few with sliced ears (from before they came here).